I gave up and sent my 73 to the shop, transmission assistance needed now

[WH23G3G]

I took  my 73 400-4 Charger to a shop that I've known for a long time. They already got it running better but there is a transmission issue as I expected when I drove it before I took it to the shop. The mechanic asked if I had a high stall converter installed, he said it was barely moving which I knew. When I drove it before I took it to the shop the transmission would surge before it shifts into gear but it wasn't rough it was smooth almost unnoticeable when it shifted to all gears. It's a remanufactured 727 that I purchased like 6 years ago when I had the engine out rebuilding it. I think it has the 11" converter because that's the flexplate diameter that I installed when I put the engine in. I noticed there is a 10.75 torque converter and a 11". The original stall speed is 2400-2700 RPM. Can a bad torque converter cause that kind of shifting issue? What's a good torque converter to install, just a OEM replacement? The cam is a KC-661 Sealed Power cam which had the same lift as the original cam or close to it. Is there any adjustments to the transmission I should suggest to the mechanic before dropping the trans?

[flyinlow]

A few basics;
Trans fluid bright red and full warmed up idling in neutral on level ground?
If by surging you mean it revs ups slightly durring shifts.....it could be the kickdown linkage is not adjusted right.
Could have a pluged filter.

The only thing all three foward gears share when the transmission is in drive is the rear clutch is engaged. If bad all three foward gears will slip. Does it back up OK?

A bad converter can cause the car not to move properly.

[WH23G3G]

Yeah it hesitates before shift into each gear. You can be sitting in the seat and actually feel the car rocking back and forth before it shifts. And when it does shift into the next gear you can barely tell it went to the next gear, it's not positive. Fluid is fine and the mechanic had it running for about an hour after he got it tuned and he said the fluid is full. I know have a small fluid leak that I can't seem to find, it looks like a front pump seal leak. But I know the venting of fluid out of the pump could run down and cause misdiagnosis of that. As for reverse I never could tell because when I drove it before it was tuned I had to keep my foot on the gas so it wouldn't stall. But I'm sure that's because of the vacuum leak and timing being out. Which has been fixed, but it's still at the shop so I haven't been able to do any testing. I talked to a transmission guy today and he said what I described sounds like the kickdown linkage is not adjusted. I tried doing the adjustment as per the Chrysler manual but I wasn't 100% sure I did it right. Plus the same procedure came on the remanufactured transmission instructions.

[ACUDANUT]

it could be the kickdown linkage is not adjusted right