THAT's creative. I'd be worried, however, about the tranny heat getting into the fan raising head and oil cooler temps during extended street use. Have you experienced that?
I don't spend much time in traffic jams, so I'm fortunate in that respect... almost always have air flowing under the Beetle. Also, have some JSC deck-lid stand offs, to let in cool air and clear the IDA stacks. Temps have been good, but again I'm mostly at 3,300 ft and sometimes at 2,200 ft elevation.