Thought I would add my experience to this database thingy...
Original motor on a TT with the serial number :- 2-204826 (not sure if it's early or late version) - Philips 110v 50Hz 250rpm 9904 111 31807 - 3 wire system Red, Grey and Blue.
Replacement motor from RS (approx. £50) - Premotec 9904 111 31813 - 4 wire system Red, 2 Grey and Blue.
Linked the grey ones together and connected it up. It ran backwards

Swapped the blue and red cables around and it works the right way

Whilst I was changing things around I took the opportunity to place some thin rubber (2mm-ish) top and bottom of the motor and then clamped it to the bracket. I then used some more of the rubber between the chassis and the motor bracket. Quite good isolation from the motor and the chassis, at least according to my screwdriver-against-my-ear test

cheers
Jeff