I am currently using an older Mopar MSD distributor(part# 8536) which uses a Chevrolet distributor cap! I don't know if they are available anymore but it works great for me. I run a crank trigger and the MSD Digital multi- retard box and phase my rotor 1/2 way between my maximum retard. Mike
I have that style dist on mine too with the adjustable rotor and cap-a-dapt that uses the big Ford cap.
I'm pretty sure the cap-a-dapt and rotor are out of production at least for that distibutor.
I don't know if they are available anymore but it works great for me. I run a crank trigger and the MSD Digital multi- retard box and phase my rotor 1/2 way between my maximum retard. 
