Re: Correct wheel offset for 12" wide rim?
The limiting factor on the mini tub for tire width is the location of the leaf spring. As previously stated there is not enough room between the outer fender and the leaf spring with the offset shackles and even offset bushings in the shackles for a 335 tire. If you go with a 4 link you will pick up additional width because your tire is next to a narrow bar (lower control arm) vs. a wider leaf spring. I went with a Chris Alston g bar (after installing dropped leaf springs) for the following reasons. It is easy to install yourself, no wheel hop, easy pinion angle adjustment, as noted you can fit wider tires and you do not need to cut the large channel in the trunk area that supports the shocks for the standard mini tub, variable ride height adjustment and variable spring stiffness adjustment (without changing springs). There is always trade offs. With the g bar, exhaust routing is more difficult. If you go this route and have not bought your gas tank, I suggest you get the one with the front corners cut out to ease exhaust routing. I have 315's on now but have room and will install 335's once the tread is gone.
68z/28, Richmond 5 sp.