2017 Ktm 350 sxf top end rebuild

I am going to put new a new piston and rings in my bike and I have decided to do the work myself. This will be my first 4 stroke rebuild(except for a 1979 z50), but I have a fair amount of experience with 2 strokes and can do one of those in a couple hours. I am wondering what needs to be done with the cam chain tensioner to reset it and if there's anything I need to be careful of when removing it. I am also wondering about how the timing marks should be oriented when it's close to tdc to make it easier to find. To get the timing right, as I understand it, when the bike is locked at tdc you remove the timing plug and make note of its position as well as that of the timing marks on the cam. Is this wrong? Is there anything specific to this bike that complicates this process? Finally I am wondering if there is anything I need to watch for when removing the cams and head, like spring loaded or loose stuff that would like to fly out. Thanks for all your help.