I installed the hand wand as per the directions to the flush valve.
After snipping off the end of the built in barb, I hooked up the hose.
While drilling out the nozzle opening to the dimension of the new valve will prevent future build ups of calcium and the flush is very strong, it takes so much pressure away from the wand; it is almost useless.
Frustrated, it was off to the home store for parts to make a tap directly off the feed pipe. I needed "another" shutoff valve in case the hand wand started to leak. (there would be no way to isolate it and we would then lose the toilet.)
It works awesome. Strong flush and wand spray even on the OEM water pump.