Water pump pulley help

[Castrumpet]

Hello everyone,
I am in the process of changing my engine (350) in my 68 stepside, over to a serpentine setup. I have found a setup from a 2002 S10 that has worked well (after tapping my passenger side head for the extra hole...) except for the water pump. The water pump on my engine (1980 model) needs to be a three hole setup on the pass side and the setup from the s10 was a 2 hole. I changed the water pump over to one that fits my engine (with reverse water flow) with the three holes on the left side, but the pulley that I have will not work. The inner diameter of the hole set up does not match. This is apparently not a common part as I am having issues finding one...

Has anyone encountered this problem? I really need a part number or a manufacturer that provides these and have no idea where to begin. Sorry for the newbie question, but any help would be appreciated.
Thanks,
Chris

[67dragtruck]

I seem to remember, there's a hole on the passenger side of the block that's supposed to be blocked off so you can use the s10 pump.

Here's the instructions for the serpentine kit that gm offers which is essentially the same as what you have there.

http://store.summitracing.com/partde...5&autoview=sku

[Castrumpet]

Thanks 67dragtruck. That is much easier than the custom water pump pulley I was researching. Seems an aluminum pulley runs about 100 bucks and takes 3 weeks to get from ASP.
Thanks again,
Chris

[Castrumpet]

As a follow up, I am not sure if my engine had been modified before, but the lower hole on the block was not tapped. I had to tap this to a 7/16- 14 course thread and cut an existing bolt, slot it and put that in because of clearance issues below the water pump. This has worked well so far and has only cost labor instead of the $125 custom steel pulley cost from ASP. They were 1 week out on steel ($100 bucks) and 3 weeks out on aluminum($100 bucks.) Not to mention the guy I spoke with was a little bit of a prick...

So, the 2002 S-10 set up worked, but I had to tap my older style heads to accept two bolts instead of one on the left side. I made a bracket to connect the top part of both brackets for more stability. (I am a little paranoid) I also had to tap and plug off the lower hole in the engine block at the water pump on passenger side, but the cost of the entire set up from a junk yard ran a total of $225 with shipping. MUCH better than the GM 1k asking price! Not to mention the A/C compressor is much better on the 02 models. I can post pictures of the setup if anyone needs more info. I am still working on some wiring issues, but that should be doable as well.

Thanks again for the help! Time to rock out!
Chris