Correct me if I'm wrong, but 6.2s/6.5s don't share the very same bellhousing configuration as all GM/GMC v-8 gas engines. According to wiki's list of GM bellhousing bolt patterns anyhow
http://en.wikipedia.org/wiki/List_of...using_patterns.
EX- The GM 5.3L LS4 V8 uses the GM metric bellhousing pattern.
I'm a newbie on here and am by no means an expert. Hope this is helpful.