Hi all. Here is what I expect will be my final update.
I have found that one of the connections on the IAC was off! I also found a vacuum leak between the new fuel regulator and intake manifold due to new hose that was too large diameter.
With both of those issues resolved I now have restored my 1993 240 to nearly normal operation. The idle is still slightly high, but now it only makes the car roll at less than 5 mph at idle in D. I will take it to the smog shop on Monday and report the result.
Many thanks to all of you who gave advice and tips. Every one was helpful. They all gave me the details of what I needed to think about and test and lots of how-to.
Good luck to all of you still searching for the answers.
My final thoughts: do not assume you have checked everything, tightened everything, replaced hoses with correct diameter tubing, and do not assume that something you did not change is fine. Check it all again.

 

all of the issues I have mentioned before in this post are gone, but I have another idle issue. I replaced the brushes in my alternator and it is now charging like new, but now when I cold start the 240 it surges from about 500-900 rpms and I have unplugged the MAF with the car running and the idle smooths out and after about 20sec the idle jumps to 1100rpm and it runs great with the MAF unplugged, when I plug the maf back in the idle drops way low to around 300rpm then goes back to surging. I also unplugged the IAC valve and nothing happened to the idle.
3 hours after it last ran today the battery is at 12.66v.

any thoughts, I am suspecting the MAF to be bad, but I want to make sure before I order parts.