On the Mac it is even simpler: you can use BBEdit Lite. In the Search box you put:

(valueOpDeltaAddsD)1(s*[A-Za-z]*):1

and in the Replace box:

12

I tried this with some full body morphs. In Poser 5 I first loaded M3 and then V3. Before editing the morphs didn't work on Vicky, as expected. Then I changed the V3 Deltas and it seems to work fine.
It's past bedtime for me now, so I'll have to continue experimenting tomorrow.