it takes an hour or two, mostly from finding the screws holding the kick panel down. I have not had any installation or startup issues with the panels I've sold so far, all have gone in without issues. I provide phone support.
The thing is about the original millennium button system, if you fix it, it will just fail again. I bought my original epic22 in 2000 brand new, had issues with the switch panel from day one. Same with my SX. If you load up the electrical system, the panels will go into blinky mode, may or may not come back. Eventually, inevitably, blinky is all you get.
Rick makes a hard switch panel replacement, definitely a good way to go, the reason I did not pursue a hard switch replacement is because you end up with a wad of switch wiring under the dash that is difficult to manage. I wanted programming flexibility for the button functions. We have programs for all of the Epic model button configs including heater, hatch and ballast controls. Ballast controls for SX allow you to fill or drain one tank, which you can't do with the stock setup. We recently added a cycling bilge control so you can leave your boat in water and bilge will run for 30 sec once an hour. Blower comes on automatically when you power up boat.
If you do a search you will see posts going back to 2002 when the forum was started (by me) about the blinky button issues. Luckily, you have options.