Here is a little bit of a variation on sonic's mod. Fist off, it is a little more difficult, but nothing that couldn't get done in an hour. I chose to do this becasue I couldn't stand putting 2 garage door openers on my visors. Here it is.

First off, remove your console under the e-brake. Good instructions on how to do that are here:
http://www.scoobymods.com/forums/showthread.php?s=&threadid=205

Once you do that, take out your garage door opener(s). I had 2, so I needed to make 2 buttons. Take the circuit boards out of their cases.

Next, you will need to locate the switches for the opener, They will look something like this...

Genie Intellicode

Old Sears Craftsman...

Once you find the switches, flip the board over and look at the path of the current and see what the switch seperates. (between the contact, and the button)

Genie Intellicode:

Solder about 16 inches of wire to both sides of the switch, on the bottom of the board.

Old Sears Craftsman...

Optional: The Genie Intellicode opener uses a 12V battery. I soldered 2 wires to the connector where the battery went, and used a vampire connector to connect it to 12V + (off of the alarm), and a ring connector, under one of the mounting bolts for the metal plate under the alarm. Inline, I put a disconnect on both, so the E-brake cover can come off, and you won't have to cut any wires.

The connectors. Being different makes it hard to plug them in backwards :lol:

Take your opener, and the wires to the door. Cross the wires briefly to check and see if they work. Once you verify that the wires work, cover the circuit board with some type of insulator (I used a sock). Cover the sock with electrical tape, and tape it to the back side of the cupholder, between the E-brake and the 2 blanks for the JDM heated seats switches. Rember which wires went to which opener.

Location...

Next, pop out the DCCD blank, near the mirror control. Purchase some momentary (push and release) switches. I used RadioShack PN: 275-644

Drill the hole in the blank that the switch requires, these needed two 1/2 inch holes. Mount the two switches in the holes. I had to flip one of the tightening nuts over to get it tight, you may want to use some glue too. Next, place the wires through the hole where the blank was. Solder the 2 wires from each opener to each side of the switches. Walk back over to the garage door, and press the new button... hopefully it works!

Next, pop the DCCD blank back into its spot, with the switches installed. run the wire between the cupholder and the E-Brake rubber, and secure it with tape, or glue. Once everything looks secure, check it one more time with the door. Works? Good, pop the cover back over the E-brake and your done! Any questions? PM me

This is some additional info and an alternative approach to this mod:
http://www.scoobymods.com/forums/showthread.php?s=&threadid=2794

Another way to get built-in garage door openers is to purchase a Homelink transmitter, and wire that to a switch or two (most have three channels, so you can use as many as you want) - the homelink transmitter is sort of cool because it is wired to car power (no batteries), and is programmable (even works with rolling code garage door openers) - I picked one up on eBay for $25 (there are usually tons of them on there - some are part of a sun visor, some are from a panel in whatever car they came from, etc. - all you do is remove the transmitter and switches, then put it where you want. I have one from a late model Lexus (note - if you need to control a rolling code system, make sure the transmitter you purchase is recent - 2000+, I think) - I used a spdt momentary on- off - momentary on switch I purchased from digikey. I wired one side to one of the channels, the center to the common terminal, and the other side to another one of the channels. I grabbed power from the lighter and used the same DCCD blank described above. The switch I purchased is part no. SW340-ND, and cost $1.55) Since the installation is very similar to that pictured above (I velcro'ed my transmitter to the back of the cupholder on the underside of the center console) the only pic I will include is the installed switch.