It may require some trial and error adjusting the dial on the flapper and observing the results over a few days.
Strategy 1. Adjust the dial so the maximum amount of water is left behind in the tank when the flapper closes but the toilet still flushes reliably.
Strategy 2. Put some food coloring in the bowl. Adjust the dial so the coloring is consistently eliminated during the flush.
The good conscientious technician or serviceperson will carry extra oils and lubricants in case the new pump did not come with oil or the oil was accidentally spilled, so the service call can be completed without an extra visit.