Switch from 56K to ADSL

Hi all,

My exchange has an RFS date of 5/11/03. I've ordered my service (with
ClaraNet as they are my technically trusted providers), and bought an
SMC7404BRA 4-point router with built-in ADSL modem. I haven't yet fiddled
with TCP/IP settings to get into the web interface to set this bit of kit
up. But I'm itching to do this. Will it compromise my current 56K
connection? Should I leave the 56K modem in place (connected to the 'phone
side of the filter) after the exchange goes live? How much of a pain in the
*rse is it to configure which would be the preferred connection? I'm
running WinXP SP1.

Thanks,

Terry