To get your wheels reasonably straight ( in the ballpark) take a straight edge or ruler and lay it against the center of the wheel hub with 8-10" sticking forward. ( or the edge of the rotor ). Then measure from the end of the straight edge to a fixed common point on both sides of the car (frame , sway bar, etc ). Mirror the process on both side and adjust the wheel position to equal amounts. Or you can just Eyeball it. Your going to want to take it in for an alignment check anyway. Just request that they center the wheel and that the steering rack is also centered (stop to stop). The only thing adjustable on a stock delorean is front/rear toe position. They will have the info in their data base.
Rear adjustment requires special U-shims. I recommend you get a half dozen from a vendor to take with you just in case. They go on the trailing arm bolt between the arm and mount bushing. They will also need to spin the bolt to verify whether it is straight or bent. To be safe, just replace them with ones from a vendor.
You will also want to remove the trailing arm shields before you take it in, just in case the fasteners cause problems.