BELLHOUSING FLYWHEEL AND CLUTCH

I have a '65 with 904 and that needed a few dings to be able to bolt it in. I should be able to get 300HP from the build. Can I assume that a '68 factory 340 bellhousing won't fit? I'd be using the same '68 4 spd too. Car has the pedals and linkage from the '66 factory set up.