SRT-4 trans wise would be a 2wd manual liberty bellhousing (dealer sells them) and that bolts right up to a supra trans. You can also do small modifications and make a dakota 4 cylinder bell work with the dakota trans.
the liberty bell has not been available for some time. you can find them from time to time.
I believe you can get the trans from a Colorado as well. there are options to do a manual with the srt-4 motor. I was pretty deep into the swap myself until I chickened out ( due to the mammoth size of the R154 ). maybe some day I will revisit that project.
for now I'm enjoying the car with a 318 magnum swap.