Don't have the P660 but I doubt you can do that with stock firmware. If you can get custom firmware on it i.e. open-wrt, dd-wrt I'm sure you can do what you want.
reply to wizkid6 You want to use the router functions or just the switch?If the 2nd one, then turn of DHCP Server and disconnect the wan cable.If the 1st one, you wont be able to do NAT etc, get a Linux box instead --"Perl is executable line noise, Python is executable pseudo-code."