there are some front ends out there, best bet would be to actually trade it in, or find a scraped escaldae and swap parts. or you could find parts independantly on ebay or your local junk yard.
I don't know anyone who's packaging a kit for the conversion, but you can get the parts you need from most any Cadillac dealer. You will need to change the front fenders, hood and grille, along with lights and a few trim pieces. It should be a strictly bolt-on job.
Sell the old front clip to a salvage yard to recover some of the cost of the conversion.