I ran a Holley projection unit on a Chevy 400 SB in my '64 Ford 4WD for several years. It was a pretty crude system -- only a TPS , vaccuum, and temp sensors, but I liked it. Now you can get a full feedback system to go with them. The only drawback to them that I see is if you travel much, and something breaks, parts are not readily available. Also parts are high. A while after I sold my pickup, the computer went bad. It was running full rich. The replacement computer would have cost 4/5 of what the whole system cost me. Needless the guy that owned it decided to go with a carburetor.
If you can get a system from something that has a 4.3 with TBI you can adapt it to your 250. That way parts are available and relatively cheap. That is what I have done on my 302. Joe
