Well, the problem in disassembling a T/C lock is compressing the mainspring. Without any special tools, I think a bench vise and two flat tip screwdrivers will get the job done. Clamp the lockplate in the vice, and start with the hammer in full cock position. Then put a screwdriver in each side of the main spring coil and compress the spring fully. A second person or third hand comes in handy here. Move the mainspring plunger out of the guide and the most difficult piece of the procedure is done. Then it's just a matter of reversing the steps to reassemble it.
Back 40 years ago when I was doing the RDV scene, I devised a spring compressor that worked pretty good. I took a (I think they are called) duck bill pliers and ground the tips down pretty thin, then cut a notch in the tip to go over the rod. Simple matter to just insert the pliers into the coil and squeeze a bit. I will look around this afternoon and see if I can still find them and take a photo.