I also wrote up an article about how to use a 6116 RAM a few years ago. With that and the clock speed adjustment above you can convert -17, -35, and MPU100 to MPU200. Best to use an NVRAM.

http://warpzonearcade.com/?p=392

As far as an adapter board goes, I've built those too.

http://warpzonearcade.com/?p=727

If you just want to convert to MPU200, it's easy enough. Just change the caps/resistors setting the speed. You could include the new parts with the adapter, then you have a "conversion kit".

If you want to offer a board that does both clock speeds it gets a little more complicated. The stern clock speed doesn't lend itself to simple solutions like deriving the clock from a $1 microcontroller. The clock on the Alltek boards is pretty similar to the MPU200 but with physical jumpers instead of soldered jumpers in the clock circuit. That works well enough, but there are a lot of passive components which add to the assembly time.

Here's another way to do it which might give you some ideas. This board converts to 6802, replaces the clock circuit, adds DS1811 style reset circuit, and adds ROM because I had the gates just sitting there anyway.

6800_to_6802_(resized).jpg