thanks strangeways , game has now stopped blowing the fuse , unfortunately still not working. when i first turned it on it started to power up then died. Getting the general illumination now without blowing fuse but the green led on A4 only comes on then flashes once, good to get some progress though ,  this machine has been sitting in my shed teasing me for a few years now.

U1, U2, U6 ROMs are ok - U11 PI is ok, U9 CPU is ok..

Re seat U7 6810, U8 5101 (careful - as static sensitive) and U10 PIA...

Re seat all the connectors on the MPU..

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