[jrmunn]

Changing points is not hard, but GMC did their best to make it that way. From what I read, the 60-66 V6's can have two types of distributers, one with a large rotor under the cap, and the other with a small rotor. Both are at the back of the engine where they are awkward to work on. Mine has the small rotor model that has the points screwed into the base under the rotor where they are simple to remove and install, but the gap adjustment requires turning a screwdriver placed in a slot while separately loosening and tightening the hold-down screw while the points are positioned where the cam lobe gives the widest separation. My experience has been that this is basically a trial and error method that one keeps doing until the gap is correct. The gap measurement is made with a metal feeler gauge.

Once the gap is set, a dwell meter can be used to see if the points are opening and closing within the specified degrees of rotation. I don't know if this is essential, but it helps me know that things are working right.

Timing should be checked after changing points, and adjusting timing requires loosening the distributor hold-down bolt , which is in a hard-to-reach (for me) location under the distributor. I use a crows-foot on a ratchet extension to do this. Once loose, the timing can be advanced by turning the distributor toward the vacuum advance housing and retarded by turning the other way.

And while you are at it, this is also a good time to install a new condenser.

Good luck with this. Original equipment points do wear out and need to be changed. More often in my case because the resistance wire that is supposed to limit ignition voltage after the engine starts is not working, which causes the point contacts to burn out more quickly. This can all be fixed by installing a Pertronix ignition system that I hope to get around to someday.

JRMunn