New hall sensor fit inside the distributor. 

Ignition car parts Ltd are one of the largest suppliers of used car parts in the UK we have a full range of car parts for classic and modern vehicles. We have a full range of New Reconditioned and Used distributors, we also offer a test repair rebuild service for any distributor.

Not sure if your distributor is faulty we can test it for you, we do this free just pay the postage back, if faulty we can repair it, it cheaper than buying a new one