Engine turns but won’t start after starter replacement

I've taken good care of our family car and have
been able to maintain it with regular maintenance
done at home for the past ~16 years, ~176000
miles.  The last issue: starter went bad and after
replacement the truck is dead...
A bit of background:
Check engine light was on, codes were for vacuum
issues, started replacing hoses (past 2 years)
engine light would go off for some time, show up
again with same/similar codes, replaced gas cap,
more hoses and all good.
VSC and TRAC lights came on, brake got really
hard and would stop with enough distance. Brake
fluid was black, flushed brake lines but no good.
Replaced master cylinder, purged lines and it was
happy again.
No lights or issues for some 3 months after break
fixes.
Then trouble started, I heard an interesting noise
when starting and I figured that the starter was
going bad. Researched and found out where the
starter is located and postponed fix due to a trip
for work. Same day I come back when the starter
died and had to tow the truck home.

To prepare for the repair I wanted to have a clean
under hood (this is likely my biggest mistake here)
so I used simple green and water to hose debris,
dust and some grime off.
I got the starter, and some help to do the repair,
the knock sensor connector's clip broke but
otherwise seems intact and making connection,
added high temp silicone to hold in place and
reassembled the intake manifold. Cleaned Throttle
body while it was out and put it back and
reconnected all hoses and electrical. The car
started rough, and idled low at first and it seemed
to hunt for idle and finally idled normally but it did
not accelerate and had a couple of miss fires.
Pulled the codes and saw the miss fires, some
vacuum so I thought (Darn should have changed
all the gaskets) got the gaskets, and replaced the
lower one for the intake and the throttle body and
resembled. It started again briefly and died. Pulled
codes and saw P1126 (magnetic clutch and likely
throttle problems).
That's when I threw in the towel and took it to the
shop where they replaced the throttle body with
one that was clearly from a donor truck and no
luck. I took the truck back to cut my losses short.
Since I've replaced the ECU, had to swap the
Immobilizer EEPROM from the original ECU to the
used ECU so it would send sparks (simple surface
mount chip swap) but it did not want to start.
So far it seems unlikely that the throttle body and
the sensors on it and the ECU are the culprit but
I'm at a loss as to what it could be. I would hope to
get some more mileage out of this truck but I need
help.
Any ideas from anyone here as to what I should
check would be appreciated.
The next steps I would take are:
Disconnect all wire harness connections and spray
them with electronics cleaner.
Get back into the Knock sensor area and check
that the connection is good. If there is a way to
check that without tearing the intake apart again
I'm all ears.
Check spark plugs and coils (don't have the tools
for this last one)
Replace the ABS control module (if not to
expensive)
If all this fails then I'm going to either donate it to
charity or Junk it but I would really hate to do that
as I think the truck is still alive in there and can be
brought back.

Thanks in advance for any tips.