Yep, takes awhile.
Yes, the piston is always loose like that.
The lines are steel, should be alright. Just make sure you get those copper washers back in for the banjo bolt.
That seems about normal for the bowl being full of crap. I swear mine had gravel in it. I would remove the fuel heater, disassemble the regulator and clean it all real good. There's a screen or two that get clogged.
Would be good to do the fuel bowl "rebuild." Basically just replacing all the orings and the drain valve. (Common leak point)
Also the filter restriction sensors are known to leak. My choice was to remove it and just plug the hole. (Wasn't going to spend 80 on a sensor that's known to fail over and over again, when it's not that important)
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