I bought a bathtub faucet with 25 pages of instructions

And I never read instructions till all else has failed. We could be in a heap 'o shit here, depending on how things play out. To be fair, it's a bit more than a bathtub faucet. At the heart of it is a substantial brass casting with four connections coming out. Right away I recognize we're in stupid land here, because there's utterly no sound reason to have more than two connections into a faucet, those being the hot and the cold. Anything more is mere status signalling. But if you want a sharp looking shower/tub combo that'll help you keep up with the Jones's, or the Kardashians, you gotta upgrade from the basics. Hence the 25 pages of instructions.