Myarc 512K card modification

[RickyDean]

I have looked around at whtech.com, but not finding documentation on the conversion of a foundation 128/512 card to a myarc card. I have two that I converted, from the above mentioned Myarc 512k conversion and it seems they worked in the past. but I cannot get one to show a led, and neither comes up when i try to do a CALL RDTEST. All the chips have been tested/replaced as necessary and I replaced the led on the one not working last night, and installed two new eproms, still not working. So I am leaning toward a bad transistor, or something. But there was rewiring to do on the back of the card to be able to use the 512k memory dram and I want to be sure this was wired correctly. Can anyone point me to a doc/schematic source? Thanks