Well then you probably still want low end but good mid and high end. Still very doable with reeds. Nearly all modern bikes run reeds still. (Big topic)
Easiest is to fix your intake situation, carb dialed in and maybe switch to a 40T.
Reeds boost low and mid range. They tend to limit top power.
OZ Reed can be good if it's the 4 petal one with the wedge shape like the one in the picture.
Problem is most windowed pistons come with wrong timing. Too much or wrong place can be worse on performance.
You only need 140-160 degrees. Most can be done via notching the piston skirt. Too much with a fistfull of throttle will case blubbering and dying.
Tape measure is fine just don't use the end as 0 use any other and have the metal end clear the cylinder so its flat when measuring. I just ussally use the 1 foot mark. Sense whre talking about intake, measure the intake from the bottom of the port to the top. Guess the deck height, should be no more then say a dime at tdc. If it lower, theirs geometry issues, if their's more it's ok. Stamp marking on the conrod helps alot too. PK80 should have a FM80 stamp.