Thank you to everyone! I at least now can select whether to use the network card or the sound card (but not both...more on that in a sec).
I never did get SMC_WD to work, but I went back to the WFW3.11 installation where the network card was working and found a folder called "Packet" that had "PKT8000.COM" in it and THAT worked great.
Turns out there is SOME kind of conflict between the network card and the sound card because once I initialize the packet driver, the sound card won't work in Windows again after that. Any idea why that might be?
Here are the current settings of everything that is installed:
XTIDE card, I/O 0x300, 0xcc00
Sound card, IRQ 5, I/O 0x220
Midi I/O 0x330
SMC StarCard IRQ 3, I/O 0x280, Addr 0xD400
Also I'm getting random application lock ups now if I have mTCP on and sound going. I also tried using Trumpet Winsock and sound at the same time, and that caused the whole system to lock up.