I got a little angry and yanked out the fuse box i pulled it apart and the inside is a mess on my 200ohm setting on my multimeter it shows .8 from the fuse holder to the pin on the bottom and its the only one that does im worried its cooked all on the ecm b fuse

 

At this point i basically have a entire wiring harness laying in my living room i have tested continuity on everything i possibley could test i havent found anything worse then a .08 from end to end i did however find that the non power side of the ecmb fuse to the plug had a 1.8 reading on the 200ohm setting

 

At this point i basically have a entire wiring harness laying in my living room i have tested continuity on everything i possibley could test i havent found anything worse then a .08 from end to end i did however find that the non power side of the ecmb fuse to the plug had a 1.8 reading on the 200ohm setting

 

What happened when you disconnected just the fuel injector connector?

 

I disconnected everything on the truck to the point that the ecm b fuse was only connected to the ecm when i disconnected the injector plug it didnt make a difference and to be sure my ecm was good its now in my other s10 which i drove to work this morning with a completely bare fuse box maxi fuses and relays taken as well the ecm b fuse still blew. As i mentioned before i took the fuse block out of the truck and checked the plugs they seemed to have been a bit nasty but the bottom of the fuse block was corroded as well so im going to get another fuse block and see if that helps then if it dont pop the ecmb fuse right off ill place the other fuses one by one to make sure its not a back feed issue

 

I've been following and somehow got lost...

You have two S10's? (Let's call them Truck A and Truck B)
You got a third ECM?

For simplicity I call it ECM, not sure what the correct name is on the 2002.

Truck A has the problem with blowing the fuse "B".
Truck B does not blow the fuse, regardless with which ECU it runs.

Truck A with ECM A - blows the fuse
Truck A with ECM C - blows the fuse
Truck A with ECM B - we don't know (I've not read that you tried that version)
Truck B with ECM A - does not blow the fuse

I would suggest to go back to the wiring diagrams.

What does Fuse B control? (Fuel pump relay?)
ECM's have more than one fuse. Usually several which are directly or indirectly controlled.
Usually 1 fuse for power supply to the ECM itself.
Usually 1 fuse for the fuel pump, controlled by a low power output from the ECU to a relay.
Usually 1 or more fuses for the fuel injectors.

To add to LesMyers advice to check out all the wiring also add the connectors and check for corrosion, unpinned wiring etc.
Then check what is really supplied by that "Fuse B" and check downstream from there. Bad ground, chafed, pinched wiring. (i.e. to the fuel pump.)
Also look out for repairs, additions of stuff to some "hot under key ON" - we have seen some weird and hilarious stuff over the years.

You said you have the "complete" wiring out... does this include the part inside the truck under the dash to and from the various boxes and the fuse box? (ECM, TCCM, HVAC, etc.)
My guess is that you are talking about the engine wiring harness from the firewall to the engine.

 

Pull the fuel pump relay and swap in a different relay and/or check for a short to ground on the terminal corresponding to pin 30 of the relay (if wiring damage is suspected). Or if the harness is out, look for damage on that wire to the fuel pump relay line. I know that on a 2000, the fuel pump relay is powered by the ECM B and if it shorts out, it can cause it to blow because I experienced it myself a long time ago and chased down this exact rabbit hole until I swapped the fuel pump relay and all the problems went away. I'm not saying this will be your problem, but it was mine and I felt so stupid for all of the time I spent tearing things apart that a $8 relay caused the whole problem...

*EDIT* -- I did find a power distribution chart for my 2000 and the ECM B fuse does only power the ECM & the fuel pump relay for my 2000. I'm not sure if the same is true for a 2002, but I would assume so.

 

And there you have it. See attachment. Not sure why they don't show a split to this in the other wiring schematic. Oops! Looks like the split was there.

 

in an 02 it powers fuel pump, fp relay and oil pressure sensor. Ive stripped all of the wires from the harness one by one the entire harness including behind the dash and have found nothing that warrants a short, no burns no bad spots the wiring is a little faded in some spots and the interior harness looks brand new and tests fine, im sorry you were confused truck A is the problem child truck B is my perfect running truck ive swapped part upon parts tested wires on truck A to no avail. Ive tested the relay port you suggested and it was 0.000 across the meter, i even tested the wiring at the fuel pump and the power wire and grounds tested off the frame ground strap were at 0.008 at the most, non of the 3 ecm i have blow in truck B once again sorry for the confusion

 

So it blows the fuse when the FP relay is taken out of the fuse box?