I'm trying to figure out how to properly use shadow RAM in the BIOS of a 386.

I have an SMC EtherCard Elite network card and an ALWAYS IN-2000 SCSI card among others (such as an SB16, modem, etc). Both the SCSI card and the network card have toggle switches/jumpers respectively to set stuff like the IRQ, ROM address and base I/O address.

I've set both cards to use different resources but I still can't get Windows 3.11 to finish the installation. It always crashes in roughly the same place but with a slightly different error (around disk 7 when you install the printer and network). I believe it has to do with a resource sharing conflict however I can't figure out what the conflict actually is. My SCSI is on IRQ 14, the network is on 10 and the HEX addresses are both set differently. My working hypothesis is that I'm not correctly shadowing these addresses in my BIOS settings but I need to check myself first before I can verify this to be the case.

First, I read that SCSI cards don't like to be shadowed at all. Therefore I turned off shadowing on the range of HEX where I set the jumpers on the card to. However for the network card, I enabled shadowing for the base address and turned ROM address to OFF/SOFT. Problem is, when I open MSD, it shows areas of memory that are unavailable that should be available if I'm not shadowing them and my windows install still crashes.

If I use the card's jumpers to assign the base I/O or ROM address to a specific area of memory, MUST I shadow that same area in the BIOS? If I don't, will it cause an error? Is there another possibility that could be causing my install not to work?

I can add that earlier on, when I did get windows installed (probably because I skipped network installation), as soon as I tried to install it from within Windows I would get these general protection faults and I could not get an IP assigned to the card. The card could ping itself but not the router and the computer would lag every time DHCP failed to work. The SMC software that checks your settings for you failed to detect the card but the card itself would light up and blink the activity lights and the drivers installed correctly too. So I think it's detecting the card and all but won't work because of some resource conflict. There are only 3 jumper positions for base I/O and IRQ so I'm limited there and "SOFT" never works so I'm not sure what to do but I'm wondering if this BIOS shadowing is the issue. By default, the BIOS had certain areas of memory shadowed, most of which I turned off so for all I know I broke something else. I do have my video card shadowed though so that's not it. It's just the general I/O memory area I'm fighting to understand right now.

Any advice on this? Thank you.