having picked it up from a local Indy's shop yesterday - shift linkage sorted out and Freon added - I noticed a lot of smoke coming from underneath the car and a burning smell.

I looked underneath (at the level just forward of the front seats) and saw something dripping on the middle(?) muffle from above (didn't seem to have any color to it and the AC has been off). Seems like it's some kind of liquid hitting the top of a very hot muffler, but if that's the case - shouldn't there be a shield between the body and the muffler? The muffler feels like it's going and the Indy claimed as much.

I am very perplexed by this and tired of the expenditures so far.

In the mean time, what would you recommend I do? I will absolutely avoid driving it until Monday morning.