The actual physical work connecting hoses to instruments, filters, etc. in the pitot static system is nothing magic or complex in the least...just uncomfortable due to location usually. Working under my A&P, I've done the filters (cartridge and foam sleeve) on a couple Cherokees, replaced a vac pump, and replaced an airspeed indicator which required rerouting hoses and reconfiguring an improperly done "T" branch in the line. The system is one of those things that sounds like voodoo until you look at it and put your hands on it. Once you do, it's amazing how simple it really is. That's true of MANY things on an airplane. Even avionics are just really "connect the dots" with wires, pins, and connectors...there's just a buttload of "dots," and you have to be careful, have patience, and do it right.
Once it's done and your A&P inspects your work and signs off on it, a leak test isn't that expensive at an avionics shop, nor is it a time consuming or difficult process, usually.
Just my recent personal experience,