THANK YOU!
Amazing, it was very easy to do. Compared to the other cartridges out there, is this an easier one? Great advice.
One more question. I'm trying to get the drain overflow stopper thing to work so the bathtub will hold water w/out a pop up drain. It is plastic and from the hole downstairs it says it is GERBER. I've tried both brass and plastic cylinders to close it off, even put some petroleum jelly on them. The plastic one almost works, but the water still drains. Any tricks? I have access right now, if Gerber is bad brand.