OzyDuster74 chassis connector questions!!

I have gone with the holley 6.4 hemi engine mounts and 904 gear box mounts as everything shuffles forward. I know i cant get the headers so will most likely have a set made, saves notching fire wall and as i am in oz postage would of been a fortune.
Question, what should i do to the 904 strength wise and what is needed to marry it to the hemi 6.4?