Thanks. But that isn't working either. I have pin 7 free and I can move move pin 8's wire to pin 6. This'll leave Serial3 free of anything. I think I'll try that for now.
It's possible you might be doing something wrong. Impossible to say without seeing the code.
It's also possible you've found an obscure bug in the HardwareSerial or SPI code. No way to really investigate without a program to reproduce the issue.
Wait, I tried switching it over to serial3, nothing. So I removed the added serial device all together. Nothing. I'm sorry to have bothered you guys. I obviously have something else going on here. Maybe I cooked one of the SPI pins messing about? Who knows. It's time for me to do a lot of back tracking to see what I broke.