I have a 94 TA that I would like to build a amp rack for. Does anyone have any drawings or demensions for the rack that goes upagainst the back of the trunk?

You can bolt the amp right to that section.

You could do what i did and build a custom box down where the t tops would be help and mount the amp on the flat part right in front. go to my cardomain site for the 87 and theres a pic there. and welcome to TFS.

You could also do like we did when I worked for an audio store in Nebraska. We bilt a box for triple 10" JL audio W0 12 ohm subs. It used almost the whole well in the rear of this 93 firebird. We left a 2" space from the edge of the rear shelf down to where the box started. We then mad a "face" that would flush mount with the amps and capacitors that were used. Then to make it wo where the subs could breath and the amps could cool we used 1/2" plexi to build an underside enclosure for the amps and caps to mount on. We put "slits" in the plexi that were a 1/4" wide to help the amps breath then we slot ported the center of the amp rack to let the bass come through the amp rack. We had to dynamat each joint where the back plate of the amp met the casing but it sounded AWESOME! I wish to this day they would not have gone out of business I would have loved to have the sketches for that design.

or you could take the lazy route...
http://www.subthump.com/acamarorack2.htm

or at least thats what it might look like