Just fired my fresh 440 in my 69 Coronet R/T. while I had the eng/trans out I make some upgrades to the 727 (by VIN trans is from a later 1969 383-2 car). Upgrades included a transgo TF2 shift kit as well as replacing the 2.9 lever with a 4.2 (a previous owner had added a part throttle kickdown). Never done any trans work, but I did everything exactly as detailed in the transgo instructions (used Munroe 727 book as well to help with the valve body). Everything appeared to go back perfectly. This includes as well band adjustments as well as the throttle position valve adjustments done exactly as described. Just over 8 quarts of TCI trickshift (Merc) brought the fluid level right up to full on the dipstick. Assume the torque converter is just a run of the mill stock unit (had a drain plug on it).

Got the engine running, but am having trans issues now. I will list some of my observations below.
When in D doesn’t seem to want to come out of 1st gear unless I totally let off the gas pedal. Have held it part throttle up to over 4000 rpm and it stayed in 1st.... way way past where it should shift. throttle may be about 1/8 to 1/4 of the way to WOT.

Interestingly if I am going along part throttle in D at say 3000 rpm (stays in 1st), above where it needs to shift relative to speed/throttle, if I downshift to 2nd it instantly upshifts from 1st to 2nd.
If I go WOT at 40-45 mph it stays in 3rd (3.55 gears and 27/60/15 rears)… doesn’t downshift.

If I roll out with gear selector in 1st and accelerate hard, but not WOT, when I bump it to 2nd the shift was slow and occurred about 500 rpm after the shift.

At a standstill it drops into gear normally and quick for 1, 2, D, and R

What I have done to try to fix things:
Confirmed throttle position adjustment was correctly adjusted
Checked gear selector adjustment
Made top rod on the throttle position linkage (stock 3 segment linkage) a total of 3 and 6 full turns shorter (from my reading this should bring the shift in earlier) neither appeared to help at all.... from drive only way it comes out of first is completely letting off throttle. With these 2 adjustments the slotted rod went from just in contact with carb stud to 1/8 and ¼ inch of slack.
Confirmed throttle opens fully (i.e., throttle lever isn’t fully back before throttle is).

Sorry for long post, but figured all these details may be needed to get to the bottom of this.

Not sure what to do at this point. Any suggestion? New to this so need some help here.