What version Plug'N Go roms do you have? I have the latest version I can burn for you. $45 shipped. It's four ROM chips. This will auto map the RAM for you as it has a built in config menu to save the settings. Works with KS 3.1+ also.
I have some doubts about Fusion Forty...
I think my board is rev1. It probably has latest roms (it seems to autoconfigure all the ram) but I'm not 100% sure. Is it possible to replace the 56Mhz crystal by a 80Mhz one and replace the 040/25 by a 040/40Mhz?
I ask because I have read here that there are two models:
http://amiga.resource.cx/exp/fusion40Is it possible to update rev1 to rev2 so 128MB of ram can be installed?
here it's stated that there are 28, 33 and 40Mhz versions:
http://amiga-hardware.com/showhardware.cgi?HARDID=213