how do i replace the magnetic pickup in the distributor?

after much cussing and probing with a multimeter, i think i've narrowed my ignition problem down to either a faulty pickup in the distributor, or a bad MSD box. since the distributor pickup is the cheapest of the two to replace, thought i would start there. but what is involved with replaceing it? how do i get the reluctor wheel off the shaft? can this be replaced with the distributor in the car or does it have to come out to do this?
thanks,
-Tim
Author: admin