Create Test netwrk using T1 WIC’s as WAN

I have a couple of available Cisco routers with single ethernet ports and TI DSU/WIC’s. I want to create a test network with these using the WIC’s to simulate WAN connectivity. Can I simply cable between the WIC’s with either a straight through (or crossover) CAT5/RJ45, to simulate a WAN link? What other ways might this be accomplihed with the given equipment, if this won’t work?
TIA