That is nice about Gen 1 easy ecu swaps. At least in the Gen1 the ECU also is the TCM all in one box, and it is special for Trac or no trac cars. landar is right about all the other ecu's in the car there are many. The one is engine control unit, and all the rest are electronic control units confusing nomenclature. Frank, also look at club Lexus for the ripple test, that is supposed to tell you if the caps are going bad, so maybe do that before diving into the ecu. But still order the caps to have them in hand when needed.
Maybe you need to purchase a wrist strap, and read up on ESD, get a soldering iron and practice a bit, then read the tutorials and go for it. I think the hardest part is dealing with the interior stuff of the car, not goofing things up and removing the ecu. The rest is easy.
When handling electronics you have to be very careful about electrostatic discharge, that is where you walk across a carpeted floor and when you touch some grounded metal object you get a spark. Even your bed blankets can do the same, it will ruin the micro circuits that work at very small voltages, those static voltages are in the thousands of volts and punch through the small molecular separation of the micro circuits.