I just removed a tremsetter from my guitar today because I couldn't get it to stay in perfect tune even after over a year of working with it and troubleshooting. To install a tremsetter, you need to (not in any particular order):
(a) drill a 3/16" hole 1/2" deep in the body
(b) bend the end of the tremsetter rod to get it in the hole
(c) remove the center spring (I replaced mine with two 47 mm springs to increase the tension)
(d) screw the springs almost the whole way in
(e) drill to small screw holes to anchor the tremsetter
(f) adjust it over and over again until you find the center point (this was a pain).
Total time installing: too long
Total time happily playing it: I never got to start the clock
On a positive note, I installed a tremsetter in my other guitar in 1998 and it has worked perfectly since.
If you are interested - There is another (incredible) alternative.
I installed an
ESP Arming Adjuster in it today (and I didn't have to route the cavity in my RG1820X, it had enough room @ 2 1/4" route). I would spend the extra few bucks and buy an ESP AA. Dive bombs/pull ups? It doesn't matter, it stays in perfect tune. To install it, I:
(a) blocked the trem in place using a deck of cards cut in half
(b) removed one of the springs to align the ESP AA
(c) drilled and screwed in the one side of the ESP AA
(d) replaced the spring
(e) removed the other spring
(f) drilled and screwed in the other side of the ESP AA
(g) replaced the spring
(h) followed the directions for adjusting an
Ibanez backstop (SKIP direction 1 - It is not unnecessary!
A cool thing about the ESP AA is that the end accepts an allan wrench to adjust the shaft distance - great for getting right up to the trem)
(i) attach the felt
Total time installing: 10 minutes
Total time happily playing it: How much time do I have left on earth?
I hope this helps (Sorry this was so long - I hope I don't get suspended for using too much space on the jemsite server

)