Well, I've definitely broken it : (

I only get 1 flash, sometimes 2 which looks the RAM has gone bad. 

I imagine I have done something while reseating or reflowing U7 or U8.

There is a fair bit of battery corrosion down there and some of those joints look a little crusty.  I cut out the old battery and installed a new one when I bought this 8 years ago.  Looks like this one might have leaked too.  I have cut it off and cleaned up as best I can without removing components.

It looks like I have done a reset circuit rebuild and an HV rebuild on it - was a while ago but it rings a bell.

So I have at least 2 problems, possibly more and many signs are pointing to the MPU.

I think I might be ordering one of those Alltek Ultimate MPUs.  What do you think? Have I given up too easily?

It looks like those Ultimate MPUs are pretty much plug and play after you have set DIP switches.  Does anyone have any experience with them?

My only other option is that a friend has a Xenon.  I guess I could put the RAM etc in his and see if it boots. 

Any other thoughts?

Thanks.
Matt.