You know what would be cool...

[Saxman]

The problem with the A-36 was using a liquid-cooled engine for a ground-attack aircraft. She lacked the durability of the P-47 and other air-cooled birds. Also, as mentioned she lacked acceptable performance at higher altitudes meaning she wasn't useable as the high-altitude escort the P-51B and later models became. THAT is why she largely fell out of use.

However the performance stats posted on this board in previous threads shows that in the MA conditions of the low-altitude furball the A-36 would be a monster. By far one of the fastest under 10k alt

[Greebo]

I did a little bit of research on cannon armed Mustangs. 150 cannon armed Mustang Mk Ias were built, initially intended for the RAF. However only 95 were delivered to the British. The rest of the order was taken over by the USAAF and converted into F-6As. The RAF aircraft saw a lot of action over northern Europe from 42 to 44. 35 of the USAAF aircraft were sent to the 154th observation squadron in Tunisia in April 43. In both cases the aircraft flew low altitude reconnaisance and ground attack sorties.

It would be interesting to see an altitude/speed chart for Allison and Merlin Mustangs. I'd guess the drag from the cannons would knock off 5-10mph.

This would probably be the earliest operational perked aircraft if it was done. I can't think of another plane which would need to be perked that was operational earlier than 1944. Can anyone else think of one?

I'd guess its a bit too rare an aircraft to ever get done by HTC though. OTOH they did do the Me163.......

[Debonair]

Did you see the A-36 movie at Zeno's?
There seem to be cannon armed P-51s in that flim that are not contained in your research.