Rider44 ,
I have a Gen 2 with a few mods and last year i ran a 42 shot , didn't have any problems . But not worth dropping a valve . change the valves and valve springs also might want to change fuel pump . I use a Bosch #69420 . Pump is go up to 400 HP mine is a in the tank and if you are using the ECU Editor by Greg Smith go 50/50 on your injector balance .
Bill