Rock-ola 477 Max Help Required

[Ribeye55]

Hi. I’ve had Rock-ola 477 Max for almost 18 years.  16 of those it’s not been working.
As I have more time on my hands now, I’m giving it a go to get working. Reaching out from UAE.  It’s been stored well, not damp etc.  Unfortunately I don’t have much electronic knowledge but I have done the following by following guidance etc from the forums.  I have a service manual with the unit.
Unseized gripper mechanism as it was jammed.  Checked what I think all fuses.  I do have spare boards and relays (apart from Play Control Relay).
I have following symptoms;
AMP does not appear to be working, however currently leaving that as a last item to investigate.
Popularity meter, the 3v cell is dead, replacement on order.  Popularity meter therefore not connected.
All lights/ballasts/starters disconnected for now.
Carousel not stopping in correct position, but reckon I can follow manual and sort that.
Test procedure for Logic Board – works.  It puts records on, however record not ejecting when finished nor eject button not working on back of AMP (under volume knob), however reverse relay on mech pwr board is clicking.
Eventually, although painful to watch and hear, record does return after some time, about 2 mins, moving very slowly. At the same time the gripper motor (nipple on the bottom) seems to be trying to spin both ways at the same time/?
After Logic Board test procedure, switch back up and Carousel turning as well as turntable, however not stopping. Continuous, revolutions.
Any help appreciated.  Be patient… Rob from UK in UAE.