Juggernut

It appears to be an access door for the oil cooler. There are two options for this door, the only difference between the two being a slightly different shape for the earlier aircraft (I can provide S/N information if you'd like). The Tamiya part seems to represent a later aircraft. I don't know why the door is bulged in the center on the model...it's possible that this was an "add-on" at a later date and the aircraft Tamiya used to develop the kit had this sort of panel on it. The NAA blueprints do not show any sort of bulge on the door (see image below). My best guess is that it's an access door for the oil cooler drain but lacking any proof, I can't say for sure. Hope this helps a bit. Image from Air Corps Library.com - accessed 01/19/2020.

I found it. It's on ARC : Aircraft Resource Center - 1/32 P-51 Review (of sorts) by Tourist.

Nice photograph. That's one I haven't seen before. I don't know why the CBI keeps being mentioned. Mrs. Bonnie belonged to the 348th FG and operated, according to historyofwar.org, from New Guinea, the Dutch East Indies, and the Phillippines; definitely not part of the CBI. Source: http://www.historyofwar.org/air/units/USAAF/348th_Fighter_Group.html

This is somewhat confusing but according to what I'm reading, the SCR-695-A IFF radio set was located behind the pilots seat armor on the floor (only on aircraft not equipped with fuselage fuel tank [it had to be removed]). The E&R manual indicates that on later airplanes there was no provision for the SCR-695 or 515 and were equipped with the AN/APS-13 IFF instead. A sure indicator that an aircraft has the SCR-695 (or 515) and lacking a view of the cockpit behind the armor plate, is a vertical pole antenna (it looks to be about 24 inches in length) underneath the right wing near the tip. The AN/APS-13 has the familiar tail mounted antenna. If the aircraft has neither the vertical antenna under the right wing, nor the tail mounted radar, it does not have an IFF system installed. I'm thinking that the battery relocation was done to allow the installation of the SCR-695-A radio suite and retention of the fuselage fuel tank, prior to the availability of the AN/APS-13 but if true, why then would the battery relocation have been standardized on later production aircraft that used the AN/APS-13 IFF; it didn't need that area behind the pilot's seat (at least according to what the illustrations in the E&R manual are showing)?

I found it on the P-51 SIG Tech Forum: The battery was relocated forward of the firewall beginning on 44-84390 (P-51D-25-NT) and 44-74227 (P-51D-30-NA). It does have to do with the installation of the SCR-695 radio set, which is the IFF radio. Source: North American Aviation "Weekly Service News", dated May 14, 1945, pages 8 and 9.

The Tamiya kit, while excellent, is a mish-mash of production blocks. There are details that belong on later production aircraft that need to be removed if modeling an earlier production aircraft but are not mentioned in the instructions (I.e., the hydraulic reservoir access door in front of the windscreen...not there on dash 10 or dash 15 aircraft ). There are also no instructions to correct/modify access panels that we're added, deleted, moved, or changed shape during the production of the aircraft. No mention of the swayback and production DFF (dorsal fun fillet)...which is understandable and very easily incorporated if one chooses. These may be beyond what the average builder will reach for but knowing gives the builder options not otherwise available. There Is a comprehensive details review by Tourist (a noted P-51 authority) describing all the detail issues with the kit. I believe it may even be on LSP someplace.

I have read that the prop suffered from vibration issues but haven't read that it was to the extent you mention. Can you give me a source for that information ? I'd like to read more about it.

I originally thought so but I'll be damned if I can find it anywhere. I can't even locate the modification paperwork for it. I could've sworn the relocation started with the block 25 production at Inglewood (NA) but I'm not finding it. I also thought the relocation was tied to a radio change as well...couldn't find anything on that either. I have yet to check the P-51 SIG site and see what I can locate there. SEE MY UPDATED POST BELOW. I did find that the practice of painting the interior aluminum with one coat of zinc chromatic primer (including wheel wells, etc.) began with the block 20 series.

And here she is in combat with an Aeroproducts Prop.... which is what the OP was asking about. Judging by the scoreboard, the Hamilton-Standard prop came shortly after this photo was taken, indicating that she flew at least part of her combat career with an Aeroproducts prop.

I’m pretty sure it was delivered with an Aeroproducts prop as I believe she was a P-51K. I’ll have to check the serial number to tell if she had the battery relocated.

I need to correct my statement. According to Ryan Toews' Tamiya A6M2 Tweak List, the prop had dark brown faces, not black. Tamiya A6M2 Tweak List

Yes, natural metal on the back of the pro, black on the face of the prop. in case you’re confused, the face of a prop is the part that faces the pilot, which will be painted black. The back of the prop is the camber side of the prop, which will be natural metal.

All A6M3’s (Model 32, 22, and 22a) were built by Mitsubishi. As far as I’m aware, Nakajima only built the A6M2 model 21, the A6M2N (floatplane), and the A6M5 series.

Are Ta152H-0’s considered preproduction models? I am under the impression, perhaps incorrectly, that the NASM H-0 was a production model....I haven’t looked at it in a long time so my information may certainly be lacking.

There was a floatation bag behind the cockpit from frame 7 (about where the aft wing/fuselage join is in your photo...as a locator for frame 7) back so painting the area black shouldn't be an issue.