I have a bracket & pulley nightmare going on right now. I bought, was told to me, a complete set of SWP pulleys & brackets off a 66 BBC (SWP)
Water pump pulley is 351680AA. I just want to figure out what I have.

I'm not sure what that pulley is for. The short water pump pulley is the same for BB and SB. You could use the SB crank pulley, its just that it covers the crank bolt. Also, you can't mix deep groove and non deep groove pulleys, the spacing is different.

Thanks Ken. Both pulleys line up, just not the brackets. I wanted to know if the pulleys were indeed SWP.

Jimmy, here is a picture I had of SWP crank pulleys that may help.
http://bellsouthpwp.net/k/s/kss396/pulleys.JPG
1 is a standard single groove SWP crank pulley for Alt. and WP .

2 is a double groove SWP crank pulley for Alt. , WP, And A/C.

3 is an add on crank pulley for SWP power steering. This pulley bolts on top of #1 or #2.

4 is pulley #3 on pulley #1.

5 is pulley #3 on pulley #2.

6 is a BB deep groove SWP cast iron crank pulley.

Can you post a picture of what you have?

I have the #2 Pulley on the crank, and the part # 351680AA is a double groove pulley that lines up correctly with the bottom (your #2)
I really want to get my car going, so I ordered a set of LWP brackets and pulleys from Alan Grove.
My problem now is I'm running headers (for the time being) and the SWP 66 P/S bracket won't work. Nobody makes a complete SWP set up and the Factory pieces available total up to over $600.
I'm learning a lot here!
I also realize why I see so many 66-68 big blocks with long water pump set-ups!