Hey y'all. The basic info on how to do this is floating around out there, but I thought it would be nice to have a pretty photoessay available for all.
This covers the mods for adjustable delay time, infinite repeats, and increased wet signal from the "Mix" knob. Plus a solution to the extra pot placement.
The infinite repeats mod: a big ol' blob of solder between that SMD resistor and the leg of the cap sticking through from the other side. Other DIY sites recommend shorting a different resistor (visible above and slightly left of the tip of the screwdriver/pointer) but I felt that one took too much travel out of the stock "repeat" knob. This one still gives infinite repeats, but you get better control over them.
The maxed out wet signal mod: short the resistor between lug 2 of the "mix" knob and that big metal pad. I used a piece of wire.
And the real point of all this mess, the adjustable delay time mod: remove the resistor between pin 6 and ground, and replace it with a pot to ground. I soldered one lug (center lug I think) to pin 6 and the other to that big ground point below and to the left of the top left screw. Like Dano says, put some strain relief on those wires, or they will snap off. Immediately.
Here's where the other "how-to's" have been lacking: delay time pot placement. I took my trusty Dremel with the 1/2inch sanding drum attachment and slowly ate away at the corner of the battery tray and the footswitch lever arm apparatus. It took lots of grinding, then checking clearances, then grinding again, etc. until I was satisfied with the result. Make sure you can depress the switch button and that it actually turns on and off.
Clearance issues: the pot pushed the footswitch lever too far down, so I put in a spacer to raise the switch board. Cured the problem of "always on" or "always off."
Put it all back together...
Still works? Good!
Make your own knobs from fallen twigs and branches. Never take from a live tree, because in the next life you might be a tree.
Here's where I got the basic ideas: http://experimentalistsanonymous.com/board/viewtopic.php?t=1094&highlight=fab+echohttp://www.beavisaudio.com/Projects/FABRack/