Is it possible to pull the pulley off the water pump? Is it press fitted? The pump I have is the same as below.

 

whay are u trying to remove pulley?.yes it is a bitch to pull of the pulley. pressed on althought the 97-98 fbody/c5 wp were 4 bolt and could be unbolted

 

I can't see your picture on my work computer, but yes you can pull the pulley. I am running an f body water pump with a truck pulley. I took a three bolt harmonic balancer puller and drilled three holes in the pulley. Its a real pain, if I had to do it again I would put some heat to it. I brought the truck pulley and f body water pump to my machine shop and they pressed it on. I believe they had to pull the rear cover to support the bearing. I tried to heat up the pulley in the oven and get it on myself, couldn't get it to go so I had the machine shop press it on. Once it was press on, I welded the holes up and painted it.

Edit: Picture was taken before I welded the holes up.

 

Yep, it's only pressed on. I used a truck pulley on a LS1 pump. The truck pulley came off with a 3 jaw puller, but there's not enough room th get the jaws around the back of the LS pump. I ended up hacking up the LS pretty bad before I got it off. The truck pulley just presses (hydralic press) onto the LS pump. Be sure to remove the reatr cover and support only the center shaft when pressing the new pulley on.