Tach housing stuck

i'm in the middle of a top end overhaul on my 78 kz 650 SR. everything has been going smoothly until i tried to pull my tachometer gear housing out of the head today. IT'S STUCK. i pulled the flat plate and holder off and then proceeded to try and pull it out with plyers, pry it with a screw driver, i put a socket on it and turned it counter clockwise with no results and clockwise with no results, it is very stubborn to turn and is stuck in there pretty good. my manual gives no advice on how to remove it. i wanted to replace my oil seal on it since i'm going through everything. any advice on this would be great. from what i've heard and seen you are suposed to be able to just pull it out, but even with turning the head on it i get no results. thanks -steve-

I have the same problem on my KZ1000MKII. It's as good as welded into the head. I've never got it off in the 25 yrs I've owned it. If your seal is not leaking, I'd leave it alone. Yes contrary to "the book", this does not have to be removed when camshafts are reinstalled.

Every time I have had to remove one I have had to tap it out from the inside.