as far as I know, all the rb20 blocks are the same
E, DE and DET is all in the head (OK, technically the pistons too, though I would presume the crankshaft is the same)
but, yes, the clutch shuold bolt right on...
Are you sure that you can't find another less heavy clutch? Not that there is anything wrong with it, but it would probably feel pretty heavy compared to your old clutch.
anyway, good luck with it.
-ebola