#1
So how long does it take? And what do you have to do? Also tell me what tubes are recommended, thanks!
Gear:

Guitars:
Takamine Gs330S
Fender Standard Stratocaster
Ibanez RG3EXQM1
Epiphone SG G-310

Amps:
Crate Palomino V16

Pedals
Ibanez TS9DX
Line 6 Tonecore Uber Metal
#2
You pull out the old tubes and stick in the new ones, they're just held in sockets. Then adjust the bias if you know how.
DRM, it's killing music.
#3
You're going to have to take the screws off the side of your amp and slide the chasis out to get to the tubes. Once you do that, you just pul out the old ones (maybe jiggle 'em back and forth a little first), and push in the new ones (the pins are aligned to only go in one way). A little non-lubricated contact cleaner isn't a bad idea when swapping 'em out, either.

Enjoy the stock ones for a while.

Stop by the Everything/Tube sticky for tube recommendations. JJ's are popular EL84's around here, and you can't go wrong with Tung-Sol 12AX7's. My next EL84 purchase will be Ei's. I've heard great things about them, now I want to hear them.
You Don't Need a halfstack.

You Don't Need 100W.

Quote by jj1565
i love you slats.