The drain plug is, I believe, either 10m/m or 12m/m. Expect the pan to retain a little fluid - probably a pint or so.
The sump filter can simply be cleaned by blasting out with carburettor cleaner - but remove it first. If you can't get a gasket for the thing (I think it only comes as a kit,) you can either cut one out of bulk gasket material, or "build" one out of RTV or Gasket Eliminator, if you're carebul.
The pan bolts should be 10m/m, but there are a couple dozen of them, so don't lose track. The rearmost ones are going to be a little difficult, with the crossmember in the way, which is why I'd advised you to drop the pan the first time, and then every third or fourth time after that (N.B. your original thread.)
I find it most useful to use a "spinner handle" or a nutdriver on the bolts when putting them back up. If you have a torque wrench that goes low enough, 84 pound-inches/7 pound-feet is PLENTY for the gasket. I use LocTite #222 to retain the bolts out of sheer habit - I don't like things working loose.
Scotch-Brite pads and carburettor cleaner will work neatly for cleaning up the mating surfaces - they're what I use on pretty much ALL gasket jobs.
5-90