2014 E92 Auto to Manual

[NLG]

First time posting, hope I do this right.

I am transplanting a 2014 Automatic Trans Corvette engine and E92 ECU into a Stand Alone track car.
I am not using anything from the 2014 Vette but the Engine and ECU.
Drivetrain is all old school (No Electronics).

My problem is I cannot get the car to rev over 4000 rpm.
When letting off the Petal - 99.6% Throttle 31% the rpm takes about 3 - 5 seconds to drop back to idle.

My question:
Am I chasing my tail by trying to get a ECU from a Automatic car to work in a Manual Transmission setup?

Any help is appreciated!

Thanks

[BurnMetal]

What did you end up doing?
I have a manual swap as well an also have the problem of not revving over 4000.