Check out the LSX Swap section on the forums, there's more info there than you'll ever need! All the questions you have and haven't even thought of are answered there.
I found it also helps to read through some build threads to get an idea of what works and what doesn't.
As far as engine mounts go, the selection is endless. You can use original V8 stands, 6-cylinder stands, 73-87 V8 stands, or many aftermarket stands. For adapters there are quite a few choices too.
Check out these links:
http://67-72chevytrucks.com/vboard/s...d.php?t=377348