jetting on that machine is the same whatever elevation because of something called dpm 04-05 revs were bad for flaking the piston rings and you would lose compression an easy way to tell is if it stalls every time you put it into reverse you know you got low compression
the right puller for the doo kind of locks on to the case so you don't have to worry about the phase but anyways if you bring it to me ill check and true your crank when it's out it.s fairly easy and i stock gaskets seals and isoflex
i wouldn't worry too much the e-tec has been run on the 600 for 2 years already and the technology is taken from brp's outboard engines i would still be concerned about clutch and engine which i think they need to improve just my 2cents
it's not air screws it's fuel screws and the more you turn out the richer it runs and the richer it runs the faster it comes down to idle. i think i would be checking the vacuum hoses for rave valves on intake side of engine cases