Removing the AIR pump will actually decrease the temperature of the catalytic converters. The AIR pump exists to continue combustion in the exhaust manifold, in order to get rid of unburned hydrocarbons in the exhaust at idle. The vacuum advance on these engines was connected to ported vacuum, which defeated the vacuum advance at idle. The late firing of the charge at idle caused the mixture to be still burning when it passed through the exhaust runners into the manifold. With fresh air being pumped in, the exhaust gasses continued burning. This caused the primitive cats then in use to run very hot as well, which helped them operate effectively.
Removing the AIR pump will increase your unburned hydrocarbons at idle, which is an issue if you still need to be smog checked.
If you remove the pump, you should move the vacuum advance vacuum line to a manifold vacuum port to get correct timing at idle. This will make your engine idle much better (you will probably have to adjust the idle speed back down), kill any off-idle hesitation that sometimes results from ported vacuum (because the distributor has to advance to the correct position when you crack the throttle), and reduce engine heat at idle (because you aren't dumping a late-fired mixture through the exhaust runners in the heads).