You can buy the MSD kit ( at local speed shop) that has all the springs and stop bushings in it. Also go to their web site and it gives you all the info on curving. I set my initial at 14 then the total at 32. So I had to put a bigger stop bushing in it. The stop bushings range from like 18 to 28 degrees. When I got my car the total timming was going aleast to 40. It is a little tricky getting the stop bushing in with the dist in, but I got it done.
www.msdignition.com
Scott