I am planning to install an 'add-on' bidet to one of my toilet fixtures. The existing cut-off valve is a gate (?) multi-turn valve (chrome) which is connected to a 1/2" copper male adapter. (the house plumbing is Copper). While I am adding the bidet, I want to replace the 34yr old gate valve with a 1/4 turn ball valve. There is a stainless steel ball valve available. My question: any issues connecting stainless steel to copper? Or should I use a chrome ball valve (assuming I can find one). Home Depot/Lowes didn't have either a 1/2x1/2 ball valve or a 3/8x3/8 one. (all they had was compression).I don't think using a threaded sch40 ball valve would look very good although it would probably be 1/2 the cost. Should I be concerned about using dissimilar metals (corrosion on the copper?)
I will be installing a Tee at the base of the tank to provide a 3/8 NPT male connection to a 3/8" 1/4 turn ball valve to feed the bidet add-on (so that I can easily cut it off while my grandchildren are visiting to avoid a flooded bathroom from kids playing with the bidet).
The biggest hassle I foresee is draining the water out of pipes to be able to disconnect the existing 1/2" gate valve, because the house is 2 story and the toilet in question is on the 1st floor.
Any advice/tips on performing the job? I'm concerned about accidentally messing up the copper male adapter when taking of the 34yr old chrome valve.