The first question I have for you is did you buy this JEEP with the motor already in it? Look on the base of the MSD distributor and find the Model #. Should be MSD 8516. Next pull the cap and remove the two screws for the rotor removal. Check the weights for rust and corrosion. Clean and put some dielectric grease on them, springs too. See weights: MSD Ignition 8628 - MSD Distributor Replacement Parts - Overview - SummitRacing.com
. Check magnetic pickup for rust and corrosion, clean if necessary. If cap and rotor any white scale on posts replace with MSD Ignition 8014 - MSD Extra Duty Distributor Caps - Overview - SummitRacing.com MSD Ignition 8467 - MSD Distributor Rotors - Overview - SummitRacing.com
Tighten the distributor hold down bolt until you can not turn the distributor. If you don't have a timing light borrow one to set the timing not by sound.