drivability issue
You know how to adjust the vacuum can. It's posted. As far as mechanical advance, ther easiest way is the Mr Gasket advance weight spring kit, and soem modification of the distributor. I'm assuming its a factory part? So, pull the unit from the car, and stick it in a vise (lightly, dont crush it). Use a set of needle nose pliers or two screwdrivers and pry off the reluctor (the 8 pointed star looking thing). Then, unscrew and remove the vacuum can, and the ignition pickup. IN the center of the dist shaft is a little brown cloth tab. Pull/remove it with the pliers. Under it is a small spring slip. It has two fingers that point straight up. That clip retains the advance plate the weights ride in. Carefully pull that clip. Sometimes they come right out. Sometimes, they argue. In any case, dont trash it. You need it to put things back. when the clip is out, you can pull the advance plate. There should be a number on the plate stamped in. That "should" be the total amount of centrifical advance the slots will allow. Most I've seen are in the 16-28° range. If you want around 35° total, the vacuum can has a number stamped ont he arm too. (or should). That's the total it can add. So, you take the 35, subtract the vacuum can: we'll say...11, then subtract what you want for initial (I like to use 15°), so what you have left over is what you need in the slots. 35-11-15= 9. So not much. If your advance plate is marked 18, you need to close off 1/2 of the slot to get 9°. So, take the advance plate to a muffler shop, and have him (carefully...) weld up the slots until only 1/2 the length is open. Take a file, flatten out the welds on top and bottom of the plate, and then take a rat tail file (small one) and round out the weld where the peg on the weight will hit. A tight spot there can cause binding, and an idle that doesnt like to come down when you slow down. Then, swap the springs per the instructions..basically, take out the heavy elongated factory spring from the weight and reatiner, and replace it with a light one from the kit. Then reassemble it all. When you're done, stick it back in, and reset initial for 15° as a place to start. When you get the curve right, then it's time to dial in the carb. All done by you, I'd expect total cash outlay to be about $25. You will now own the biggest part of an FBO/MP/Summit performance ignition conversion package.