[R_WALDO_86]

I believe that your motor is a 307 and not a 407, probably just a typing mistake by you.. no big deal... If i were you i'd pick up a hayne's repair manual at autozone... i have one for my jeep, vw bug, and Delta 88. They go through a complete tear down and rebuild of every component.. i believe the book covers all rear wheel drive gm cars from like the seventies to 1990. It should be all the help you need... btw they are like 15 bucks