Hi guys,

Pretty much as tittle suggest I'm considering putting an 454 big block into my 1973 G10. Currently its SBC 350cu through a 350 auto. I was hoping to drop the 454 in and hook it up to the existing 350 gearbox.

I've done a bit of digging and i am aware that there was a factory G30 in nineties. So it obviously fits to certain extend. The potential issue I think i have is that mine being a pre 78 is the earlier line of gen3, one of the changes they made between mine and the 90s models was a "larger dog house". I presuming this wasnt just the dog house itself but the hole it covers too. So I'm worried despite a BB fitting the 90s g30 it wont actually fit in mine. If its just going to need so bashing / triming then it might still be a goer but i seem to think they actually moved the frame rails to get the extra size of the dog house. I'm not really thrilled at the idea of chopping frame rails and would probably just go a different route if that was the case.

I appreciate i'll likely need to run at least the g30 spring and probably the whole cross member but thats bolt on right - even to a '73 ?

I'm hoping someone with a bit more concrete knowledge could wade and confirm if it'll fit at all and what kinda things will need done.

Sorry this seems like a bit of repeated post - ive done a search and there are a lot of threads about it, but they're all discussing the later (post 78) van