OK - I'm pretty sure we have resolved the "dual 5101 RAM" issues as used on a Stern MPU200.

We designed up two adaptors.

One allows the use of a 6116 RAM on any Bally board that has a single 5105.

The other board allows the use of a 6116 on a Stern MPU200 with 2 X 5101 RAMs.

Basically we took the info from here: http://warpzonearcade.com/?p=392

and tweaked it to suit our boards and made it a lot neater.

They both would plug directly into the empty "U5" position on the MPU and have 3 short wires coming from them.

Next board run we will knock up a couple and give them a try.