Hi All. (86 Toyota Pickup, 5 Speed, 2wd)

[turbothrush]

Originally Posted by mackerel

It looks like the 3.90 is the fastest thing rated for the 1 ton chassis.

I was thinking just keep the 1 ton housing ,axles and brakes etc. and swap out only the diff to get the better ratio. the gen 4 2wd 4 speed manual is 3.07 and is supposedly an 8 inch or 3.41 from a v6 truck. Maybe worth checking out if there is a pick-a-part or pick and pull nearby.
I just mention this as food for thought since I think you have such a cool project. I've got a v8 tundra and my payload is 1000 lbs less than yours.