Solder on the npt adapter : profit.
Looks Great!!!
I must get one of these NYSpeed approved vanitys
if you are messing up the internals of the valve you are using too much heat…probably because there is still water in the line that you are boiling off on the pipe side while overheating the valve side. a dry copper pipe and fitting/valve will heat up quickly without injuring any of the internal parts…and once it is hot enough to melt the solder on contact with the valve/pipe you can usually finish the job without maintain heat on the valve or fitting.
lots of people sit there with the torch blazing and a pool of solder below the fitting when there is actually very little space to be filled between the pipe and fitting
Heh… that would be me, on my first attempt anyway. It’s a learning process. 
By the 3rd valve I installed it was about 30 seconds and I was done. The more I work with soldering copper the more I realize why it was such a popular choice for plumbing. It’s too bad copper had to get so damn expensive or it would probably still be the preferred method over plastic because of the smaller diameters and ability to take it apart for repairs.
i agree…i will only use copper on my own house, but i have made the switch to PEX for my investment properties. when something goes wrong or i need to add something on it is just so much easier to just shut off the supply and cut into the line and not have to worry about draining everything before making repairs or adding on. the tools can be pricey but they easily pay for themselves in saving on headaches. typically i’ll run copper for a bit into the wall/floor/etc then switch to PEX so at least there is some rigidity at the valves.
my only problem with the PEX is that it can be difficult to deal with in a tight space if you have to crimp a connection.
So what is the 14/2 doing? I like unions at shower valves since they will inevitably be replaced
Electricians were nice enough to run the light over the toilet past the valve to the switch just above it, with zero slack. Cartridge style faucet so the valve body should be good for quite some time.