This is a pretty good write up http://www.off-road.com/toyota/doa22re.html I would swear that some company back east had a conversion kit available (I just searched and didn't find it though).
Do you have a donor truck in mind? Keep in mind you'll also need an EFI fuel tank (I don't know if the pump itself will swap into an carb tank). The parts you need can be found on www.car-part.com or (from personal experience I know these guys are good) www.flagauto.com . You'd have to check into any other fuses, etc. that might be need as well.
This may seem like a shameless plug, but, I have the EFI stuff out of an 88 4Runner. I (think) have the upper and lower manifold, throttle body, injectors, computer and a brand-spanking-new factory EFI harness (man, was that PITA to get) off of my other truck.
Mark

EDIT...The tranny is different on carb trucks. You should check out the info Marlin has in the tech section for more details.