Yep just look there are two different HD versions for the 064 did not know that I've got the older version on mine which don't really matter there great saw's know mater how there set up is.
Make sure when you go to put the cylinder back on to make absolute sure that the transfers have no interference with the case or you'll be doing it all over again.
I think that will be OK I use blue lock tight on all my D compression valve plugs they don't leak and never come loose ever. So I'm guessing the lock tight you have is the red?
I think the only place that you can use jb weld on a cylinder is on the intake port just because it's getting air and fuel to help keep it cool but anywhere else on the cylinder I'd rather not push my luck.
Well I've got a spare one for mine and if were to sell it I wouldn't let it go for less than $60 but I rarely ever see them up for sale and they are getting scarce here big time so I might be light on my number. Lol.