Suppose this is nice-to-know for the factory Iron-pump folks...
This issue is no matter when you use the REVISED modern aluminum pump:
The GMB pump has been improved by Flow-Kooler model # BRA-1649 sold by Summit:
The divider plate's function has been welded to the Impeller.
So, the impeller has a sheetmetal hat welded to it now.
So, I took out the OLD GMB aluminum pump, and installed this UPDATED pump into the Timing Cover with factory divider plate. No clerance issues.
My car hardly warms-up.
HIS