Thanks Sam and all on this board for some great advice and help.
I finally got the ringer working at half past midnight, put the phone back together and then couldn't stop ringing it from my mobile.
Reminds me now of watching Cagney & Lacey in the 80's, hearing all those fab rings in the cop shop!
Shame that in the UK our phones go 'ring, ring.......ring, ring' as against 'r i n g.....r i n g' as they do in the US.
Can't believe I paid £6 for it, brand new in box with wiring diagram and new plastic inserts.

Mike.