Mopar circle track question

Nice looking car!! This will be a purestock at a local track, North Central Speedway in Brainerd, MN website is www.racencs.com. I may have found a 74 Charger with very little rust that was used once for an enduro race. I have not had a chance to look at it yet. Have to wait see what it looks like as far as rust. I'm told it's solid. That class has 112 inch or longer wheel base rule. I will mostly be racing against mid 80's Impala's. I have raced IMCA hobby stocks and did pretty good and ran a B-Mod last year. My biggest concern is building the Unibody rollcage to make sure the frame and body stand up to the abuse. I think there is enough torsion bars made that I should be able to find a combination that will work, same with rear springs.