I have not looked at a T56 out of a GTO. I have owned a T56 out of a Camaro. The shifter was several inches back of a Muncie location and the picture looks like the GTO shifter is even farther back.

You need to do some measuring on stock shifter location and GTO location relative to block surface.

 

Measuring will kind of have to wait till the engine and trans are installed unfortunately. Or I could measure from engine mounts back and get a guess.

I don't necessarily know where the shifter "should" come up through the floor. Google is my friend.

 

Maybe someone here can post a measurement from the bellhousing surface of the block to the stock Muncie shifter location. That will give you a starting point.

I assume you are talking about a 68 Chevelle.

Note the location of the shifter in the picture.

The question is, will you be happy with a shifter that is eight or ten inches farther back between the bucket seats?

 

If your T56 shifter is straight up, it's approx. 4 in. further back than a Muncie. That gto shifter looks to be an additional 3 or so inches. Can you spin that thing around to face forward?

 

Iirc, I came up with a dimension of 17 in to the rear of the inside of the firewall as a desirable location for a floor shift in my 66 with a bench seat. None of the Mustang and Camaro units worked at all.

 

The T56 has three shifter locations. If Im not mistaken.

1. You use the stock GTO location.

2. You can use the stock Camaro location.

3. You can use the Keisler location.

In my truck I used the camaro location, but had to get a shifter cup to make this application work.

The Keisler location is the most forward one. Im not sure it ever came about or if it did not sure they continued making it. It was in the location that in the Chevy truck locations the shifter would come up through the stock 5 speed location.

 

The GTO has a longer offset block lever under the shifter. To use the Camaro shifter you just swap the offset piece for the Camaro one.

The forward location (not created by, nor thought up by the aforementioned scab) is not too bad to do with the aftermarket kit. The thread on one of the C/K truck sites on how to do it without trans. disassembly tells enough.