That doesnt change the fact that your information is wrong. NAA clearly called their own plane 'Apache' before it was ever called 'Mustang.' When the USAAF put the first P-51 into service it was called Apache. So you can say the first offical service name of the British version was Mustang but only for the British and only after delivery.
Many years ago I read an interview of Atwood and Kindelberger where they stated they chose Apache because it would give their fighter a ferocious yet noble image and they were somewhat surprised that the British chose the name of (what they considered to be) a problem wild animal with terrible traits.
Guppy: There were precisely 300 Mustang 1s built. They came looking for 300 P-40s and they took home a better fighter. I dont think you can argue against 150 as being insufficient given some of the other planes and vehicles in the game already.
My understanding was the first order of Mustang Is was 300 with a second order of 300+ more.
I have no problem with wanting an Allison 51. My bigger issue is it seems to be another one of those find a way to get another 4 cannon bird in the game. I've never seen anything to suggest the 4 cannon Mustang was ever used for anything beyond ground support and tac recon.
The first Mustang kill was Yank in the RAF Hollis Hills in a Mustang I over a 190 prior to Dieppe. The Air Commandos in the CBI had P51As that saw a fair amount of service. The A36s in the MTO were used a lot.
My bigger issue is clouding the wish for 4 cannons behind asking for an Allison Mustang. I say the same when folks start the howl for a 4 cannon Spit. I love Spits and their history, but a 4 cannon Spit doesn't fit in the game anymore then a 4 cannon Mustang in my opinion.
If it's all about an Allison Mustang then the more numerous combat examples would be just as welcome