to site your existing router on the bench? Then you could simply connect PCs to it via the LAN ports on the back.
Your 'main' PC could access the router via a wireless PCI adapter.
Alternatively, if you can't move the router why don't you just run an ethernet cable from one of the LAN ports to a socket box on the bench? Then you could plug computers into that. Running a cable wouldn't take long, and you would save the cost of buying any more hardware.