Its not the bad
For someone like myself that is not the most mechanically inclined, underdrive pulleys were probably the easiest thing to do, besides obviously an air filter. Just make sure to tighten your bolts to the pulleys after you put the belt back on. I forgot to do one of mine and the next day it got ripped off and broke my water pump. Its just like tightening your lugs again after you put the tires back on the ground. For the H-pipe, make sure to get the emmisions tube kit for it. Way back when, my friend and I put an h pipe on my 90 lx. We were running all day long to get parts because we were clueless. The kit is basically like a garden hose that connets your emmisions tube, which you have to cut off of your stock cats, to your h-pipe. Also, the night before, make sure to soak your bolts of the cat (from headers and from cat-back) with WD-40 or the like. It makes your life so much easier. Depending on age or rust, you might want to replace those bolts as well. I would suggest it. Flowmaster American Thunder is the way to go after that, just my opinion. Have fun.