Well I have to say. I had the same problem. I live in SF and last week I drove to Sonora and it was about 90 degrees and oil temp was around 255 degrees pushing a grade. Needless to say, my mechanic installed Scoops on the driver side air intake. We also installed a 74 super beatle air fresh fan to suck in extra fresh air from a tube that runs up to the air vents. My temp now going up the altimont Pass 225, at 70MPH with a head wind. Absolutely one of the best things I could have done for the HIPPO (next to installing Ken Black racing juggs 96mm). Hope that helps.
We made the scoops out of sheet metal from OSH.
Hippo 1972 Westy