That would certainly be the easiest thing to do.
If you don't want the 98 PC to see your corporate LAN
and can easily make some quick changes to the PC that is on the corporate LAN
(and reverse them when you are done) then set the new machine with networking including File & Printer Sharing, a workgroup name that matches your corporate LAN
(workgroup or domain) name but IP
and subnet mask that are out of that range so, for instance, if corporate uses 192.168.1.x and netmask 255.255.255.0 you might want 192.168.10.x and 255.255.0.0 netmask for both the PCs.
To make sure you get good comms between the two, put entries in each PCs hosts file with IP
and PC name of both systems on each PC.
Note that hosts is located differently on 9X and NT systems
9X - \windows\hosts
NT - \windows\system32\drivers\etc\hosts (or WINNT)
Share the root of each hard drive on 98. NT systems will already have a share as C$, D$, etc.
If your corporate machine is NT based, you will need to have the 98 PC log on with username & password and add that information to your local users if you want 98 to see the corporate machine.
98 should have the share permissions open to anyone.