Free shipping on selected products

[Steve Doherty]

I want to use the UPS shipping by weight to have UPS automatically calculate
the shipping cost. But, I also want to have a "special offer" for a limited
time for free ground and 2day shipping for 20 selected products only. Is
there a way to do this?

The only way I could come up with was to switch to simple shipping by weight
and set those products to zero pounds, and set 0-.99 pounds to be 0$ for
ground and 2day. But, problem with that is that I have to set a price for
everything else. This method does not let me use the auto calculate by ups
feature.

Any ideas?
Thanks.