The North American A-36 Apache and early model P-51 Mustangs had a slightly different profile from the more familiar P-51D, which hasn't been terribly well captured in existing kits. While most agree that their 'D' is a pretty good representation probably based on the Tamiya 'D', the ICM Allison-engined Mustang has a certain number of shortcomings. Basically it is a mish-mash of a kit. It is boxed as a P-51A, but has the narrow air intake above the nose of a Mk.I or Mk.IA/P-51. The wings have the aerodynamic fairings ahead of the ailerons typical of the P-51B/C - although it should be perfectly possible to do something here with a sanding stick. More importantly and probably impossible to correct is the fuselage profile, Allison-engine P-51s having a shallower profile than the Merlin-engined variants - some 3 ins from canopy top to fuselage bottom on the real thing according to Mustang researchers and specialists on the web.
Nor does the kit feature locating lugs, holes and pins, and it looks like the fit will be rather 'hit n miss' as the fuselage parts are warped. I've seen this kit described as a " sort of a hybrid between the AM mouldings and Tamiya mouldings, quite odd in fact ". Perhaps because of the hybrid nature of the kit, you get lots of spares box bits eg. it comes with props and so on for a P-51B/C, two clear instrument panels, different types of exhausts and other details not used in the P-51 A.
(Below; A-36 at Duxford - a good view of the slotted retracted airbrake in the wing upper surface and the flattened elongated air scoops, both upper and lower)