I am at the same point. Trying o buy a used PCB. If it works great--if not I will try to get it rebuild. Do you know anyone who rebuilds/services the PCB? Thanks for the response. Installing the headers looks like a real chore--how many hours did it take? It is on my to do list along with new suspension.
Keep on Keeping on--
Unfortunately I couldn't begin to tell you where to find someone that would service the pcb. You might be able to have toyota reprogram it for your specific mileage, but they may be funny about that.
Total hours spent working on removing the old exhaust manifolds and cat pipe, then reinstalling the headers and modifying the cat pipe....around 18 hours. I would suggest spraying everything down with a GOOD penetrating oil (kroil,pb blaster,etc) a day before starting the removal. Also, have a sawzall with 8" blades handy in case you get to a bolt that just won't come off.
All the manifold bolts came out easy peasy, it was the ones that bolt the manifolds to the crossover pipe that really are going to give you hell.
Tools that really helped me out for removal,
Sawzall w/8" blades
3/8" drive breaker bar
12" x 3/8" drive extension with wobble end
12" x 3/8" drive extension with straight end
1" x 3/8" drive extension (used a lot)
Angled long handle 3/8" drive ratchet with swivel head
Female Torx sockets (for removing manifold studs)
3/8" drive stubby ratchet with swivel head
Set of metric swivel sockets
3/8" to 1/4" drive adapter
1/4" to 3/8" drive adapter
1/4" and 3/8" drive swivel adapters
Set of metric ratchet wrenches
1/4" drive ratchet w/deep sockets
6" x 1/4" drive extension
3/8" drive metric deep sockets
Set of various length pry bars.
Ball peen hammer
When you go back on with the headers, you'll quickly find out just how big your arms are, and how good you are at reaching behind your head and wrenching in the blind while laying under the vehicle.
When you get to that time, shoot me a pm, I'll give you any tips that helped me out if you get stuck.