[joedoh]

welcome! Thats a great looking truck!

scotts IFS is not a Mustang II, I think they even market it that way, and its got better geometry and more adjustement than a mustang II so I think you will be happy with it. scotts has a lot of experience with these trucks so make sure you get the right setup for the ride height you want.

the torque tube/trans/rearend, even the leaf springs are part and parcel, meaning if you change one you have to change them all. the torque tube rear axle pivots slightly so if you change the axle, you change the open driveline and that means change the leafs and the trans too. there was an open drive piece I think on the 3600 with the 4 spd granny trans that can be used on the 3spd 3100 trans, but the 1:1 top gear wont be a friend on the highway, so an overdrive trans will probably be what you want. but again, that means changing the rearend and leaf springs too.

to that end, i have heard good things about the speedway rear leaf kit for these trucks. using the s10 rear you will need to move the perches on the axle slightly. again, get your ride height in mind FIRST.

speaking of the highway, the 216 definitely doesnt like to rev, iit has babbit bearings and oils by splashes, if you really want a highway cruiser consider a full pressure oiled engine like a 54 or later 235. its not 100% necessary, the 216 will be ok if you keep the revs down.