Re: Merc & Johnson
Mercury is and outboard. Mercruiser is an I/O (aka Sterndrive) don't confuse the two.
Johnson is an outboard only not an I/O (aka Sterndrive) OMC, however, was the parent company of Johnson, and OMC Sterndrives.
Ford was not used until 1970 by Mercruser, OMC didn't use the Fords till 74.
Now the fun part. OMC Sterndrives did have a model 150 in 1965 and 66, it was a Kaiser V6, not a Ford V8.
So what you are getting is basically a bunch of parts installed in a hull by a bunch of previous owners. What those parts are really doesn't matter. You will probably have to replace it all anyway. If Mercruser, the parts are NLA, if OMC, parts for the Kaiser are NLA, some stringer parts are available, but until you get the boat and can post pictures of what you have talking about it, using your terminology and the sellers terminology is a waste of time. You nor the present owner have any clue what any of it is or what it's called at this point. Which makes it impossible for us to give any kind of an educated guess on what you are so set on buying.