usually the pulling truck HP that high was measured on an engine dyno so it's FWHP whereas many of the drag racer HP numbers are from wheel dynos.
At least, that's my opinion as to the difference.
I'd venture to guess that the engines in some of the racers like green machine, Jimmy Dale's, TS's White Fury, the Scheid Rail, Banks truck, etc. are making "in the neighborhood" of the same power the mod class pulling trucks are.
C-ya