Well so far I have a few parts picked out and I think it is time to order them to do some testing.
MCP23017 for interfaceing.
ISO7241CDWISO7241CDW Digital Isolator
16-350000-11-RC SOIC-16 to DIP-16 adaptor
ULN2003AN DARLINGTON TRANSISTOR ARRAY, NPN
Will have to order some of these in and do some testing and see how things operate together.
Just have to figure out the voltage feeds required so I don't fry things.