Split it at the bellhousing. Unhook throttle and choke connections, wiring, clutch rod, etc. May need to support the fuel tank, if bolted the back of the engine block.
A nice level garage floor is a big help. I usually support the front half,and roll the rear away. Be sure and wedge the front end on the axle to keep it from pivoting.Block front wheels fore, and aft.
A heavy trans. jack, or HD low cart is great under the rear half. Just have to block and shim to get the correct height to keep things level.
Once apart, it is pretty well in the wide open. I believe the flywheel is still recessed on these models, so no need for an alignment tool. Although once it's going back together, you may need to release the clutch, so as to let it properly align.
Check the pilot bushing for wear in the crankshaft. We always put just a dab of bearing grease in the dimple of the clutch shaft. A bit on the end of your finger, and just even across the front of the shaft.
I like to use longer bolts, like 8" of the same size as the bellhousing bolts to align going back together,as guide pins, so to speak.
Just don't force the shaft through the clutch plate. It will spring it. On my smaller models with live power, (engaged with clutch) I engage the PTO,and turn the PTO shaft with a wrench, to help align. You can feel the teeth of the shaft fall into the grooves in the clutch plate.
Some shaking, and jiggling, and it should go right back together.
I'm sure I left out something, but that's the majority of it. Not as bad as it sounds...,although the condition of the rear engine seal may provide you with another repair.
Even an I&T manual will get you through this, if you have none other.
