cutting the firewall whats to gain?

[57sailplane]

well,

i am thinking of getting started back on my truck again.
since its in its raw form i want to make all the mods i can now. question is how much is there to gain to cutting the firewall to set the motor back. and how far back is recomended. if i go this rout i will probably cut to fit a big block. need to read the nhra rules again as its been a while since i have read them..


later andrew k