I don't think you'll have a problem with the t-5 pushing or pulling the weight of the AD truck. They moved around firebirds, camaros, mustangs, jeep cherokees, s-15 and astovan loaded with people without out problems. S-10's and S-15's even towed loads with t-5's, so within reason you should be okay with yours.
As far as the clutch goes, don't buy one until you've got the original sm-420 clutch in your hands and know the size and spline of your T-5 input shaft. There were a few different diameters and your's might be 9 1/8th or 10" or 11" and you won't know til you look at the old flywheel and clutch. There are a few different input shafts on the t-5s depending on what you got it out of. If its from an s-10 chances are its a 14 spline x 1" input shaft. When you look for your clutch disc the hub should match the input shaft and the diameter matches the flywheel and clutch cover. For example, "9 1/8" & 14x1"
