Distributor problem

Help!

I have replaced the rotor arm on my V8 distributor. When I removed the old one the central spindle lifted up by about a quarter of an inch but dropped back but now the rotor arm sits slightly too high to get the distributor cap back on.
Has something slipped out of place lower in the distributor and is there a way to resolve this without having to remove the whole distributor?

You have popped the shaft off the balance weights below the base plate. Its a simple job to refit and can be done with it in engine, have a look round on forum its bee n explain ed many times����