Ok first off.
When you are dealing with an engine problem the number one rule is to start simple. And follow what the car is telling you.
Now so far you have been suggested to check:
TPS
ECU
Distributor
Relays
Grounds
IACV
MAF
This is nearly ever portion of the electrical ignition system on the motor save the igniter, plugs, plug wires, and coil.
Do not make things difficult.
If the ECU is throwing a maf code. Assume it is the maf. Find out what each voltage for each wire should be, and see if the MAF is functioning properly. I can see you are frustrated replacing distributors, wires, relay's, tps's, IACV's, and ECU's when the ECU is telling you it is a maf problem.
Just some advice, keep us updated, search around for proper maf voltages and diagrams. Don't mess with anything else until you do this!
Best of luck my friend.
Dudeman