We have figured out you have to use the I6 250 mounts in order to keep the 3 on the tree 3 speed and drive line all in the same place. everything seems to to work, same bell housing same motor mounts.
My question to someone that has already done this same swap is..... what headers to use to get around the clutch linkage ?
The truck does already have drop spindles and is a little lower, I'm thinking the long pipes might be a little low, if they will even clear the linkage.

 

I had a 62 Apache with 4 speed, had custom exhaust put on it, you might be looking at the same.

 

250 mounts must be different than me 292 mounts. I made me own for a 396 BBC I rebuilt. Moved engine 1 3/4" forward so I could use HEI distributor. but the engine mounts for a 292 wouldn't work even on a small block . The 250 must have different mounts than 292