6.2 to sm 465 that a big block chevy is attached to?

can i bolt up a 6.2 in place of where a big block 454 was? its a sm465 tranny?

Yes.

The 6.2 (and, for that matter, the 6.5) were designed to go wherever a smallblock/bigblock would go. So the short answer, as FMJ so eloquently put it, is "yes."

It's been many years since fooling with 454's. I remember that they do bolt up without a doubt, but didn't the 454 use a different (balanced) flywheel/flexplate? I seem to remember they were big block specific. For example you would have to have the 6.2 (or smallblock) flywheel??? Been many years/beers ago. Maybe i'm wrong just thinking outloud.

The diesel forum on CK5 can answer this. I've got a thread there fairly recently about this.