3.2 Waterpump bolt hole won't line up.

[Freakinadamant]

1993 Rodeo LS, 4x4, Auto, 3.2L. The top right (driver side) bolt hole of the new H2o pump does not line up with the threaded hole of the engine - about 1/4" off. I also noticed this with the old pump that I had taken off as well. The last person that installed it had to bore the hole toward the right in order for them to match!?? Being the Royal pain that it is to install these things, I'm wanting to figure out what's going on before I modify the new one. Could someone have installed another block or cylinder head (?) at some point in time from another model or something possibly?

The reason I initially began replacing the water pump was due to the common tail-tale coolant leak from the lower front/center area of the lower timing cover. I fear the bolt-hole offset could have been contributing to this in the first place. Is there any other common (or not) reason for coolant to be leaking from here? Thanks.