From what I understand, the 292 has a standard Chevy bellhousing pattern, so you should be able to bolt up newer automatic tranny's. Also, the crankshaft for a manual tranny has two dowel pins, one of which you will need to remove. Also, you will need to drill your flexplate for 1/2 in bolts.
Not too much modification for the upgrade.
I'm not sure bout your other question.
