here's some t-5 info, if anybody else was interested:
http://www.5speeds.com/t5/
So far it seems like the Ford Mustang t-5's are stronger, and they got the world class versions before gm did. I'm still looking to see if either the guts of such tranny are compatible to be swapped into a GM case, or if the gearbox could just unbolt and be put onto a camaro bellhousing. As a piece of trivia, the T-5 on the turbo 280zx is supposedly a ford bolt pattern where it adapts to the bellhousing.
*edit* found a flathead Ford page that desribes using a 4 cylinder S-10 gearbox to upgrade to a t-5, since the 4/6 cylinder GM trannies used the ford style bellhousing to main body bolt pattern. The inverse of that should then hold true: If I get a ford t-5 gearbox from say a 5.0 mustang and bolt it to a 4/6 cylinder bellhousing, I should get a decent strength gearbox on a chevy bellhousing. That assumes a few variables: the 4/6 cylinder bellhousing will bolt to a 350, and said bellousing/tranny combo will have the right length input shaft to operate the clutch correctly...
http://www.flatheadv8.org/t5-swap.htm