Reverse Light Switch

My '98 CSE has a problem with the reverse lights. You have to push the shifter rather hard to get them to go on, and just the force of driving backwards (spreading the gears and pushing reverse out a little bit I imagine) is enough to shut them off. It's not safe, so I want to repair it. I've read up on other forums, but I figured I'd ask here if anybody has any pointers on how to go about changing the reverse light switch, if that will even help this problem. I know it's on the back side of the transmission case (I think I can feel it with my hand) and I know it has a sealing washer.

So, several questions.
1) If I take it out, will transmission oil drain?
2) Will replacing it really help? Does the switch plunger wear down over time, or is it the inside of the transmission that's wearing?
3) If I need more depth, can I use the switch without the washer? I've heard of this having been done, but I am dubious as to whether it will provide enough seal.

Thanks to anybody who can give me some insight.

Anybody? Where can I even start looking for some kind of guide to the transmission? A c900 gearbox is no problem for me, but I've never even been inside one from a 9000. Can anybody recommend an online resource (or an EPC or WIS (what is a WIS? I am too old) to download) to aid in figuring out a gameplan for fixing this, before I dive in?

Thank you!

The WIS (workshop information system) would have instructions for sure; the EPC would mostly just give you part numbers with possible cross references.

I had the same symptoms on my NG900 and replaced the switch, which completely solved the problem. It's a different gearbox, but the same switch. I did not need to drain the oil because the switch was above the fill level.

Thanks, Oscuro! I fixed it. The problem was, indeed, the switch itself. Compared to the new switch, the old one's plunger had seemingly lost its springiness, so it completed the circuit at a much lower depth. I ordered a new switch off Rockauto for $11 and put the thing in. No oil came out, but I should probably change my gear oil now that I think about it.

Euro, since you have just done this can you advise how to remove the electrical plug from the switch?
Just feeling around it I haven't been able to determine how to release it from the switch. And hello to
another Vermonter, I live down in Pawlet, but have spent much time in Burlington.
Thanks, Bob