Big Lazy, I am happy with mine. I've thought about someday changing the rear gears, but it will run down the road between 55-60 pretty comfortable, (not overly reving the engine) like it is, so I'm not sure it's worth the extra $ for me.
The original 4-speed tranny is great, runs down the road like a champ, and would pull a house, if I needed it to. Clutch/pressure plates, and bearings are still readily available, and inexpensive.
The rear end, other than the gearing isn't a problem.
For the most part, I use both my trucks for weekend pleasure, so neither really sees alot of highway use. The 250-six sounds good, runs good, and is different than everyone's SBC V-8.
I've had 3 different vehicles with 250's. Never had a serious problem with any of them, and never put any of them "down" before logging 175-180K miles.
Good Luck
