Hey all, 1st time on this Forum. Hopeful someone here has experience and can share potential resolve to what's going on with my truck.

Sorry for long post but wanted to provide as much info so as not to have folks reply with things already done. Thanks in advance.

Preface:
- 5/01 purchased stone stock 75k miles
- 03 DTT Trans, shortly thereafter Edge Comp and F1 (now FDI) Mach 1.8 injectors 389hp/800tq
- Spring 07 Mach 5 injectors and QD 64/14 w/wastegate 525hp/1000tq
- 09 new VP.
Last summer/fall 2020 I sent the Mach 5s back to FDI to get freshened up (they had over 140k on them). Immediately after I installed the injectors (and I mean same day on initial drive post install) the truck began stalling when placed from P or N into R or D.
Truck was running fine until I installed the freshened up sticks. FDI suggested too tight torque converter or weak VP, after explaining to them DTT trans fine and VP new in 09 they said only way to eliminate injectors as reason was to build new set.
In January 2021 I decided I wasn't up for changing injectors myself in the cold/snow (live in N/E PA) and since I just purchased another home and needed the truck fixed quickly to move and etc., I had FDI ship injectors to guy who built trans in 03 and figured I'd have him go over trans while it was there (at least 150k on trans since he built it).
Since then:
1- New Mach 5s went in, along with new BOSCH (stock) injection tubes - still stalled.
2- Trans inspected, Rev band down to metal, trans pulled for teardown - friction disks worn and etc. Had new built trans with triple loc converter (200 rpm less stall on bottom end just in case...), billet flex plate and input shaft, all new internals and electronics - still stalls.
3- Since VP was 12 years old and the original one only lasted 10 years (and to eliminate cause of stalling - you know how finicky internal VP electronics can be sometimes poof they go and sometimes they play with you...), install new VP - still stalled.
4- Trans builder ran his Chrysler software and no codes, all sensors good - in essence nothing wrong anywhere? He also had a spare 99 ECM that he connected to see if mine was not telling his software the truth - still stalled.
5- Finally said enough is enough, picked up truck and drove home on 3/30 from VA Beach to North of Philly. Understand it may take a bit of fiddling but you can get it going and once its moving it runs fine "as long as" you go right from D to R. The rpms abruptly drop from 850 to 500 and just as abruptly back to 850, if rpms don't jump back it'll stall.
6- 4/5/21 installed new crank sensor - still stalls. Old one had 6 less ohms than new, I didn't think 998 vs 1004 ohms would make any difference but the old one was out and new one in-hand. Kicked tools back into garage and closed the door.

What the ____ is going on?
Just remembered a few things that might be useful
1- Before sending to trans builder (after stalling began) I unplugged, checked for corrosion (none anywhere), cleaned (anyway) and reconnected every plug/connection in the engine compartment.
2- Also made sure grounds were clean and tight (not just visual, removed fasteners cleaned ground ends and where they affixed to the body).
3- Oh, Batteries (both) were new spring of 2021

Appreciate your replies,

Joe McCaz