Supertorque timing belt conversion question

[DeWitt Harrison]

I'm considering converting the MC engine in my 1988 5kcstq to
use the Supertorque timing belt while the head is off. I understand
that all the toothed pulley items must be changed as well as the idler
or belt roller pulley. One thing puzzles me. The p/n for the oil
pump changed at the same time (mid 1989?) for some reason.
It changed back in 1991. Can anyone shed light on this? Does
the oil pump p/n have any bearing on the Superbelt conversion
issue?

Thanks.

DeWitt Harrison
Boulder, CO