Different size rims

With tire selection being what it is for 15" rims, is anyone running a 17" on back and 15" on front on their '67 thru '69 Barracuda. Just wondering what it would look like.
I've contemplated doing this when I get new wheels for my duster after my disc brake conversion. can really only fit 25" tall tires in the front, and I'd like to run 27" tall tires in the rear. I really like the vision 148 wheels. with the staggered height I'm considering, the sidewall height on the fronts and the rears would be the same (something like a 215/60R15 and a 235/55R17 or 255/50R17).....problem is finding a tire that has the correct sizes. on tirerack only a high mileage (600+ treadwear rating) general altimax RT45 comes up when you search for 215/60R15 & 235/55R17.....since I only put on 2-3k miles a year, figured I might want something grippier, and they'd still last me a decade.