[geezer#99]

I chained it, you don’t have to.
Find somebody you trust, put the park brake on, have them hold the brakes down and put it in gear then check your timing.
Or just turn your idle down. If it wants to quit just advance the timing a touch. Leave the distributor loose enough to move but tight enough to not move on it’s own.
Once you find out what your actual initial is then set it at 14 and lock down the distributor.
Try that and tell us what your actual initial is.