will it fit

I fit a 400M in mine. Car is long way from driving but the main issues have been dealt with. The question is do you want an easy swap or are you up for a project. It is as doable as other non-standard engine swaps. It's all in the details.

1st is bell housing. I have no idea where mine came. My plan was to weld one up. I may still do this in the future after everything is going. It is a bit heavier then typical ZF bell housing.

2nd is headers. Deck height is 1" taller so the headers will not align in the suspension. You can cut and re-weld the originals or you can build a set from scratch. No big deal there is you can do that kind of fab. My headers go over the suspension and are not even similar to the originals.

3rd, engine mounts. The 400 mounts are different then the 351 BUT>>>> One side on mine was embossed and could be drilled and tapped. Engine mounts were not that hard. It is something I can work on lightening latter as well.

4th is header to gas tank clearance. I am building my own for the right side so I can make the clearance what I want.

Rest of the issues are minor such as engine dimensions. Same distance front to back but the head does get tight around the right wheel well. Still fits though. Taller intake which means screen unlikely. Clutch actuation, Water tubes, etc. Small stuff.

Figment during strip down: