Hey BMP - 258 motors rule . They made them thru 1990 . Find one thru an auto salvage yard . Shop around. Get a low milage unit with everything on it. Yards frequently remove alternators and distributors - get extra money - . The last of the 258 had serpintine belt systems - nice. You can drop this engine in one afternoon and be on the street next day. Go for the Centerforce clutch system w/a lite flywheel. No HD clutch - just a daily driver unit. I am talking with Crane Cams for Roller Rocker Arms for our engines. They are sending out a prototype next week to check out. These will be able to be installed without any machine work. Also talking with them for a roller camshaft kit for the I-6 . That may take a little time tho. Go for it ! - brien