I have a T42p with a dead CMOS battery. I'm trying to replace it, but I'm having trouble opening it up. Two of the screws aren't coming out, and I may have slightly stripped the screws. I bought a new screwdriver set specifically for this purpose, so I'm sure it's not an issue of using the correct size screwdriver. Does anyone have tips for removing the remaining screws holding the keyboard in place?

Put some pressure on the business side of the keyboard with your finger opposite the screw you are working on, so you can apply a little more pressure on the screwdriver. Maybe that will help hold the screwdriver blade in the difficult screw. And, sometimes a small flat blade will hold a partially stripped screw when the Phillips won't.

As a last resort you can use a drill to remove it, google "site:forum.thinkpads.com remove stripped screw drill" and you'll find a number of threads on this topic.

Cheers.

I know you said you have a new set of screwdrivers, but in my experience a good quality, not worn out, full-sized screwdriver can do wonders. There have been quite a few times when I stripped a screw with my tiny "precision screwdriver", and a full-sized screwdriver got them out first try. (That was before I learned to always use full-sized drivers, of course. )
So, if you have different screwdrivers with the appropriate tip, try them all. Maybe one of them will be a better fit.

See this: viewtopic.php?f=2&t=81210

Thanks for the tips guys! I managed to get the screws out!