If you're going to do it, might as well go 3" per side so you can run modern, high offset rims. Offsetting an inch means custom offset rims($$) to keep everything inside the fenders with no significant improvement in scrub radius that the modern rim would provide.
Custom upper and lower control arms would be require for the front. A later model B body wagon or C body could be done for the rear, but may require cutting the housing tubes and rewelding the ends as well as cutting and resplining the axle.
The increased leverage created by the lengthened suspension will also necessitate a step up in spring rates to maintain comparable wheel rate. This is a big potential negative if you are autocrossing. You can't put enough spring under the nose of a mopar already and reducing its effective rate would not be a good thing performance wise.
Not impossible, but not easy. Only real gain I could think of with all that work is improved scrub radius and maybe wider selection of inexpensive wheels if you redrill the flanges for a new metric bolt pattern.
