ORIGINAL: nick 30

i knocked the rear plate of the can (hold the motor in your hand and just tap the shaft with a hammer) when the magnet assembly comes out, you have 3 brass shims at the rear and 2 brass shims plus a nylon thrust washer at the front, take 1 shim from the rear and replace with another nylon thrust washer, put the plate back on and tap it home (lining up the shaft with the bearings)

On the bench, it runs a bit cooler so the next step would be to drill out the plates for ventilation
its a shame the shaft is'nt longer so you can put a fan on the end to draw heat away along with the watercooling jacket