Water pressure/booster pump problem - please help

Hello all, my name is Jason and I am a licensed contractor / handyman. I have a problem with a bathroom remodel where the shower now has a 4 foot tall metal box on the wall that includes 10 jets that shoot water at the user as well as a normal shower head. The problem is, that when the user is showering and has the jets on at the same time, there simply is not enough pressure. I bought an indoor water pressure booster pump, but upon reading the directions, I have discovered that the water temperature maximum is 104 degrees F. My plan was to install this pump between the hot water heater outlet and the rest of the house.(therefore boosting the hot water) Unfortunately, the temperature is not my only problem. The pump I bought says that the operating pressure for the pump is between 23 and 50 psi. Isn't normal water pressure between 50 and 60 psi anyways? If that is the case then this pump is not strong enough. Lastly, the lines in the back of the metal box in the shower as well as the lines in the walls of the house are 1/2 inch. The outlet from the hot water heater is 3/4 inch. I have been told that since the intake and outtake holes on the pump are 1 inch, that I would need to make the rest of the lines leading to the shower 1 inch. I simply cannot do that. That is too much work. Is it possible to have more than 60 psi going through a standard 1/2 inch line? If so, what pump should I use and where can I get it? Thanks for the help. - jason