I should clarify about the PC Card. Don't confuse the SRAM Card with the internal SRAM DIMM Module when you look it up in your Maintenance Manual. Lookup the "Memory Card", which can be a battery backed-up SRAM Card or an ATA Flash Card. These days it ill likely be a Flash Memory Card, or a Compact Flash Memory Card which plugs in to a PCMCIA Adapter. Confused yet?

Question... did you use the same physical RS-232C DB-25 Connector, and simply change the settings. If I remember correctly, you need to physically move the internal cable which goes from the DB-25 Connector to the Motherboard,s RS-232C connector. It's probably connected to Connector JD36A and would need to be moved to JD36B. If one of these connectors is vacant, then that would be the case. It should be hooked to JD36A currently and JD36B is vacant currently. I'm not positive about the PORT Assignments, as I'm usually hands on and I would simply figure it out on the fly. The layout I described above is only the base level layout. Yours may be different! You would need to look and see.

I hope I helped and didn't just make things confusing. Usually I'd just repair the board and be done with it.