Totally confused.

Find a 73 to 76 dart sport, duster, get everything off the front, and as far as rear end depends how much horse power , why not go with an 81/4 then you have matching bolt pattern front and rear .If you sold the 83/4 you would have enough to buy everything you need , and money to boot i bet.

This guy nails it. The later stuff has the larger bolt pattern, and the better ball joints, and NO questionable engineering (Not all swap kits are questionable, but some sure are) and it's drag n' drop, OE parts. Easy peasy. A simple weekend job if you are slow.

MY large pattern rear axles (from Strange, IIRC) didn't change the rear offset any, except possibly a minute amount because I specified that I wanted to run "big car" rear drums for ease of parts availability.

Except the bushings and rear axles, my Mopar chassis is ALL Mopar. And it was deliciously easy to make the change.