I continue to find it strange that people do massive change to vehicles as I suspect you are with your 4 Bar only to drive the vehicle maybe on weekends or just to shows.
What I mean is that you could go the 'ultra-cheap-route' as I did and change out my '49 4.10 differential for a '57 3.90, add a '62 Muncie .70 overdrive which yields 2.73 in third overdrive. I have about 55k miles with this configuration, is a daily driver only vehicle, and I just returned from a 900 mile round trip.
That said, I have kept in my files a 1990's article that pops an 8.8 Lincoln four bar with bags (they say its stronger, lighter and has a ton of gearsets w/limited slip) into an AD truck like ours that together with a modification up front is probably the route you are headed.
Good luck with your journey I'm going to follow this thread to see where you and it go.
Regards,
Cosmo
~ Cosmo
1949 Chevy Half Ton
Rocinante, like Don Quixote, he is awkward, past his prime, and engaged in a task beyond his capacities.
"...my good horse Rocinante, mine eternal and inseparable companion in all my journeys and courses." ...Don Quixote, Cervantes
"If you come to a fork in the road, take it."...Yogi Berra
"Rudeness is the weak man's imitation of strength." ...Eric Hoffer
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