Quadro 570m driver oddities...driving me crazy!

So I've been trying to install some newer ForceWare drivers on my 15.4" T61p the last few days, and I do understand the usual process of replacing the .inf and have actually done it tons of times before with no problems; however I'm currently just about at my wits end.

Basically, the Lenovo drivers install just fine but every other version I've tried (with the proper accompanying LaptopVideo2Go .inf) will start the installer like normal, but when it shows that it's installing the driver it takes a much shorter time than usual and then finishes without installing anything with a "system has not been modified" message at the last step of the wizard. I've tried different methods for installation such as going through device manager and pointing to the appropriate .inf, but that always fails after finding the device in the .inf with a "file can not be found" error when it tries to find whatever other file that apparently isn't there or referenced properly.

The only moderate successes I've had have been a couple of versions of the XG mobile modded drivers that actually did install, however they break LCD brightness adjustment; likely because of SmartDimmer being in the .inf, although I've tried taking it out and then installing with no difference.

I've already been through, over, and under the various .inf's and am just about out of ideas for what to try next. I have a hunch that there's something missing in the driver archive that's referenced in the .inf but I've already tried different versions downloaded from various sites (including nVidia.com) with no difference. The last one I've experimented with was the latest 169.12 release.

Any thoughts or suggestions? Hackez care to chime in?

Thanks.