83 bbi timing

Have had my bbi for about 3 years. Put about 2-3000 miles a year on it and it has run fine, except it pings at 5000rpm and smells rich when it runs.

dinoplex recently went out so replaced it with MSD 6a ignition, blaster coil, and new msd 8.5 wires. Also replaced the plugs, rotor, and distributor cap.

I checked timing this morning and discovered that when timed, flywheel mark stays at A5 and I cannot retard it any further to get to AF or PM1-6. If I fully advance the distributor, it also stays at A5. If I incease the throttle to rpm above 1000, you got it, no matter what rpm, the flywheel A5 mark always appears under the strobe.

Any ideas? I would guess I have a frozen distributor (and probably have had it the entire time I've had the car) and and need a rebuild.

Mark
(put this on both ferrari forums in search of answer so pardon redundancy for some of you)