How to remove/upgrade modified drivers when 2 monitors are attached?

Emile

Hello,
A question for you the Gurus :
I run with 2 monitors attached to my GF4 TI4600.
When I try to remove an installed driver and clean the config so that I can install a new one I cannot re-config my GF4 TI4600 so that the 2 monitors run well .
I cannot config the nView Display mode correctly and have a primary and secondary display with different refresh rates, resolutions, .....

So what I do now : I install the XG drivers one "above" the other and it works.
Before I take a "restore point" in case of.

Any recommendation how to proceed with 2 monitors attached?
Thanks in advance.