Here we go again...
I *think* all '04s had the 48RE. 04 is a weird year because you had both the SO engine and the HO engine available (not to mention the CA versions of same). My guess is that yours has the 48RE but there may be some early SO (standard output) engine configurations that still had the 47RE.
You need to do some searches here for transmission threads and make some calls to the builders. Usually each guy that chimes in here will put in a plug for the transmission THEY went with as the best, and frankly, if you like your new transmission, then it IS the best.
And following that logic, my personal vote is for DTT. (single-plate TC, modded valve body "livestock version", uprated clutches, band struts, billet servos, billet input shaft, double-deep Mag-Hytec pan)