Easy. I believe all single point and breakeless Mopar built advances mount the same, different vacuum ratings over the years. Get one for a 67 so it's a "non smog" advance.
This can be done in the car, but I won't and I've done it. So pull the distributor. No excuses. If the car ran good and you don't know where the initial timing was, check timing with a light before you yank the dist. Notice which way the rotor is pointing, and about where the vacuum advance is pointing. Refer to the photos below
1--Pull the obvious (2) screws out of the advance mount, and gently pry the advance away from the roll pin index on the side of the case.
2-- Look at the photo of the breaker points dist. showing how the advance pin fits up under and into a hole in the advance plate
3--Remove the screw for the pickup coil and move it to the outside, to give you a little more wiggle room
4--GENTLY pry up on the advance plate with a screwdriver. Notice that in the photo, ONE FINGER is being used. Do NOT force this very much, as there is a small clip on the bottom of the pivot pin on the advance plate
5--Work the advance out of the plate and out of the distributor.
Reverse to install, set your reluctor gap to .008" (inches, not metric) with a NON metallic feeler, IE brass, which O'Reallys had last time I checked, drop in the dist. and set timing!!!
