Update - swapped over coin doors and all is good.  The coin door button that didn't want to work is working fine on another machine and the new coin door is working fine on the machine that had the problem.......uhh I think that's right.

For anyone interested, I will have 2 x GnR machines for sale in the next week or two.  I would like to sell them as working project machines, I am just trying to nut through a few things at the moment.  If all goes to plan, they will need a clean, re-rubber etc.  Shoot me a PM for more details if you are interested.  Price will depend on how much I end up spending to get the machines running to an acceptable level.