The later model transmissions won't fit on the 235/261 engines, without an adapter.If you take you're bellhousing off and look at the engine you will see that it is about 8 inches wide from top to bottom. There is nothing to bolt a later transmission to.Someone makes an adapter, it's been talked about here before,do a search for transmissions and you may find it.


Tommy
59 apache 1/2t
261 short stepside