Buffalo could cut a 3/8 or 1/2" groove. I went with the 1/2" which works fine with my adaptor plate mounted early style water pump and a/c compressor. If you note by my pictures in the Webshots album, I fabricated my own alternator mount which sandwiches under the thermostat housing and allows me to run ONLY one belt over the waterpump. I saw no reason for placing extra stress on the pump bearings by doubling up on the belts. The a/c compressor runs directly off the HB and I haven't had any problems with excessive belt wear. To date I haven't felt the need to add the Toyota power steering which will run off the 2nd groove on the a/c compressor.
As Vetteguy pointed out, getting your belt alignment dialed in is an issue. That's just one of the reasons why I went with the adaptor plate mounted pump with the pressed on pulley. It lines up perfectly with the balancer and addresses the inherent issues that pop up when you use a later model 235 in your pre-55 truck. Being that the 2 groove balancer protrudes to the front more than a single groove, and being able to run a larger diameter, multi-blade fan to handle the extra engine cooling, I found that the so-called "short water pump" and it's lower mounting position created fan interference problems with the balancer. I even went so far as to fabricate my own WP pulley but scrapped the short WP when it didn't solve all the cooling issues and created a whole new set. Running the adaptor plate and the early pump addressed and solved all these issues and allowed me to run a full 15" 6 blade fan.
I genuinely think that the engine clearance issues as well as the single groove HB, sway a lot of folks towards dropping in the SBC. Addressing and correcting these issues will make your 6 cylinder truck a pleasure to drive and an attention-getter at the shows.
Dave
