gen/water pump/fan belt

[30-9]

GM thanks that's a beaut!- However, I've been through this many times. The only real way of telling is if I could look at the top of the bell housing, which I can't.

My heads say 59AB, so lets assume its a 59ab. Even though that's not a good indication. Can anyone tell me the size. Does anyone have size / part number for NAPA?

I would still be curious if the size is any different between the two engines.