pulling a slant 6 out without the tranny attached

Yeah, you'll definitely want to support the transmission when you pull the engine away. It PROBABLY won't drop when you unbolt the engine/flywheel, but will when you pull it forward away from the converter. So I'd strongly suggest a floorjack with a piece of plywood as big as the transmission pan between the jack and pan to distribute the weight. Once the engine is out you can bold a 2X4 across the front of the trans and resting on the frame/suspension. I'vce also seen pictures of wire running from the top trans bolt holes looped over the wiper studs, but I've never done that.

Good luck.

PS - I'd also suggest a shop manual or Haynes manual to give you an idea of the overall process.