I'm going to be putting a "GM" serpentine belt kit on a friends '80 vette soon.  I noticed it the instruction manual that this is a reverse rotation water pump setup.  So I now have a delemma. 

Check with March Pulleys I am sure they have the proper serp belt kit, make sure that you water pump flows the same way.

 For what ever its worth the Vintage Air Front Runner bolts right in to a C2-C3 Corvette. There may be a problem with the bottom Pulley and the Frame. There was an artical in Vette Fever and they had to modifiy the Frame on a C2 but mine Bolted right in. I'm sure a Reversed Fan and Clutch is avalable but most People Me included go with an Electric Fan setup at the same time. Dewitts Radiator and there Spal Fan Setup is the most common and works good.

I went with the Billit Specialties Front drive assy. It uses the reverse Edelbrock water pump. I had to heat the front cross member frame with a rosebud torch.....the hollowed out area......to allow a greater clearance area for the front pulley on the harmonic balancer..........lots of work to hammer and grind to make it look factory. I then used Be-Cool electric dual fans to cool the radiator.   

I think I missed why you are changing to a serp belt system?

ok...here's the deal. The GM system is already in possession. He didn't want to spend $1500+ for a serpentine belt setup. So he went the GM route.

I was just looking at my clutch fan, I have never done this but, what about unbolting the fan from the clutch and flip it over??? I have reversed electric fans from pushers to pullers this way but I don't know if this would work without trying. other than that add a puller fan to the inside of the rad and remove the other clutch fan...this I have done and works fine you can add one of two electric automatic switches...one can be installed in the haed or one that mounts to the rad.

What a PITA!