What besides bad ECM or bad PROM could cause this? - Is there anything else that could cause this error? Possibly faulty distributor or.... I found this info: # the ...

Is there anything else that could cause this error?
Possibly faulty distributor or....

I found this info:
# the engine was just started, and
# either of two specific PROM locations do not contain the expected value. (One location should have 1's in the odd numbered bits and the other has 1's in the even numbered bit positions.)

Where are the two specific PROM locations??
Maybe I can check them....

Ive taken the ECM and PROM out and thoroughly cleaned them with electrical part cleaner. Put ECM back in truck and still getting the SES code 51

Called the dealer and they discontinued making my PROM and told me I'd have to look elsewhere. I have no idea how to get a new one specific to my truck.
If I bought a new ECM with PROM included (junk yard) what are the chances it will work on my truck??

No idea. Both parts have some identification codes on them but if you are just buying from a pile of parts on a shelf, it might not be an easy task to get the correct things.

Well I found some places to buy the prom chip but Im not going to until i rule EVERYTHING else out first.