Do you mean a stock manual to a stock automatic? That's rare.
We switched from stock 5 speed manual to 4r70w (automatic with full manual valve body). The 4r is almost standard issue for getting into low 10s and 9s. Rated to 1000+ hp, only 3 forward gears, and built strong enough for transbrake launches.
Now that car has been removed from the street, we have just switched to another automatic, the powerglide, which has only 2 forward gears.
Manual to auto is not bad either, but you'll need an engine/tranny portion of the wiring harness for certain. The manny harness can't be modified to auto without a mound of work. You'll also need to install a cooler and lines. You won't have the lockout solenoid that requires your foot on the brake to get it out of park. I haven't done one, but it can't be too difficult.
I think im gonna go with the tr-6060. I saw that steeda had a upgrade kit that came with the transmission but i need a clutch with 26 splines and is rated for 550 rwhp. Has anyone put this trans in and what clutch did they use.
If anybody want to do the manny to auto swap here's a fairly complete list of parts:
powertrain control module (PCM) for auto
engine/tranny spacer plate
auto pedal box (without clutch pedal...I have a couple here)
transmission sensors that plug into harness (may be on the tranny)
Note: You will reuse the driveshaft and crossmember. The bolts that hold the tranny to engine have a couple that will need to be a different length than what you had before. This list is pretty much complete other than some small **** like trans fluid and some minor hardware. Oh yeah, you'll need a pretty, new skirt!
On '05-'06 cars the MT pcm can be used. I tried to do the same in an '07 car and at the time nobody could re-engineer the thing for me. It's been a couple of years though. Maybe things have changed. The same guy I had change over the '05-'06 pcm was the guy that couldn't do the '07 for some reason.