sader dog,
If you use your original clutch housing, flywheel and clutch assembly, the rear of the engine has tyo mount in the same location. Depending on your 261, you might have to adapt the front mount (maybe by using your original front mounting plate - maybe someone who hs done this will post).
The major possible problem is the water pump pulley/shaft protruding too far. Maybe some else will comment on this.
The lengths of the 216/old-235/new-235/261 blocks are the same. If I am wrong, we will hear about it.
Tim
