Pete,
If I lived in Melbourne, and I had the enormous amount of talented pinball fixer peoples that u have in your part of the world, I would throw some nice alcohol in the fridge, and invite a few of the guys over for a quick hands on help/few pointers.
Surely, one of the forum members could volunteer and come over and help you out. This is a make it or break it repair/replace job that needs to be done perfectly to finish off all you hard work and put the icing on the cake, so to speak.
Dont be shy guys, someone step up and help our good mate Pete out.
* first one to apply gets a cold beer i reckon !