1)Yes, sorry, not enough coffee. Cam in block would be easier, is what I meant.
2) the map sensor signal in those is a 5v signal that is a variable frequency that should be 150-153hz koeo (depending on baro pressure at the time of test) so good luck. If you have the means to measure it, it will drop as the vac gets better all the way to 80 to 90hz at good idle.
3) There were many gear ratios available in those, its usually stamped into a tin tag on one of the diff cover bolts.
4) OBD2 started in 1996 in most models. (A couple cars in 94)
Pats was a few years later.
Ford PCMs got easily tun-able after 2004
Not sure what to suggest, if you get new enough to be awesome, you have computer network stuff to contend with. (My Bronco is running a 2003 based control system and I had to build a harness with 3 of the modules to make it run and shift. (PCW, GEM, and HEC) not trying to discourage you, but I had over 150 wiring diagrams between 1979, 2001 and 2003 model years to get everything working)
Do lots of research before you start, there are a few places selling stand alone systems, (all the groundwork is done)
I wanted to build my own, but there are many options.
4) The 4.0 swap will be great when its done, but it is a mountain to climb.
Have a few crown and waters (or whatever your poison happens to be…coffee works too!) and ponder a while.
The 2.9 isn’t bad either. There is nothing that can’t be fixed.
With yours its time to put down the shovel and re start, we must have missed something. Online diag is very difficult as only one of us can see the results Of a test and often small bits get missed in the info transfer.
Just my 2 cents
Cheers