I have a T5 that I'm gonna put in my 64 "one of these days." IMHO, it's a great choice. I prefer sticks over autos, and I'm not really a burn-out kinda guy, so I'm not too concerned about the trans taking major torque. But the OD is the big seller for me.
But, it's not exactly a "plug-and-play" install. If you haven't seen this yet, I'm sure you'll find it interesting:
http://www.67-72chevytrucks.com/vboa...d.php?t=313954
And, welcome aboard. Always nice to have another 60-66 guy here.