I know, a lot of people think v-amps are shit but I like mine, so ya'll can fuck off.
ANYWAY, that said, it's always bugged the shit out of me that the pedal is retarded. A two way pedal to toggle between 5 pre-sets?
So, seeing a 4 way pedal (Behringer FS114) in a store for a really cheap price, I hatched a maniacal scheme to attach it to my V-amp 2.

And this is the tutorial on how to do it.

Also, it would work with a 5 way pedal/home made pedal, too...

Anyway, you'll need these things:

Wire clippers
Wire strippers
Screw driver
Soldering iron
Solder

Pliers would help too, with holding the wire while soldering.

Step 1: Strip Wires.

Take your clippers and cut the end of the 4 way pedal's plug off.
Then strip the individual wires.

Should look something like that when you're done.

Step 2: Disassemble V-amp 2

Taking the V-amp apart is just a matter of unscrewing the 5 screws on the underside of the casing.
There are also 5 screws keeping the circuit board attached to the upper plastic casing, which don't actually need to be removed, even though they have been in the pictures.
If you really want to completely remove the circuit board from the casing, you'll have to pop the knobs off the front. It's pretty easy, just use a knife and push it between the knob and the plastic case.

When you're done, should look something like the pictures.

Step 3: Soldering the Wires

The coloured wires are going to be soldered to the circuit board.
The letters in the picture correspond to the letters on the buttons on the other side of the v-amp.

The coloured squares in the picture are indicators of which wire to solder to which piece of solder on the circuit board.
They're in groups of two, it doesn't matter which one in the group of two you solder the wire to as long as you make sure to keep the solder from joining up with some other soldered part of the circuit board.

The brown square is for the ground wire. The bare wire without a coating. You can solder that wire onto any of the eight little blobs of solder in the brown square. It only needs to be attached to one.
Before soldering you should cover the ground wire with electrical tape or heat shrink tubing.

It's also a good idea to glue the lead to somewhere on the casing, just in case it gets caught on something, to make sure the soldered wire doesn't get pulled off the circuit board, after it's all put back together.

When it's done it should look something like the second picture.
Yeah, I've never been too good with solder..

Step 4: Cut Out a Hole...

Put it back together, and BAM, you're done.

Making the hole just a little bit smaller than the thickness of the wire is a good idea, so any pulling on the switch pedal cord doesn't pull on the soldered wires.

Also, if the wire clippers aren't working very well, the soldering iron is always a quick way to put a hole in plastic...
Just try not to breath in the fumes...

Anyway, good luck, enjoy.