thats a load of .. dung.. i very much doubt you could run a 13:1 compression motor with an alcohol cam (it has very high dynamic compression since methanol si 120 octane)
you will most likely run into detonation and loose all 527 horsepower to an engine faliure...
with a change of cam, carb and intake you could propably get it running on premium and booster.... but it will be a radical engine, 13:1 CR is a strip only/mostly engine..
but if you want a 383 with a stock 400 crank in a .40 over block and sportsman heads are your fancy, buy it..
besides.. how many passes does he have on it?
otherwise check your other options...
www.racingjunk.com and a bunch of others