First lets talk reel and bedknife. Sounds like you need the reel adjusted to the bedknife (or cutting bar). The reel & bedknife work like a scissors to cut the grass. There should be minimal but consistent contact all along each reel blade and the bedknife at all positions. Basically the reel just "kisses" the bedknife.

The reel is adjusted by loosening the bearing holders on each side of the reel. The rear bolt on each bearing holder is a fixed point and the forward bolt can travel through a slotted arc, which brings that end of the reel closer to or further from the bedknife. Make sure you scratch witness marks on the sideframes around the bearing holder before you loosen anything so you can return to the original setting.

The reel is checked by taking strips of paper (about 1" x 4") and checking the cutting action of each reel blade against five or six points along the bedknife. If you are not cutting, CAREFULLY adjust that end of the reel closer by gradually moving the bearing holder. I use a drift punch and a small hammer. Check and recheck, and then finally tighten all bolts to lock things down.

If this doesn't get the reel where you want it, the next step is to backlap the reel using Clover Compound. This is an abrasive grit suspended in grease. A layer of compound is spread in the cutting area of the reel, the reel is brought closer to bedknife, and the reel is rotated backward to grind or lap the high spots off for better reel to knife alignment. Repeat and recheck. After cleaning off all the compound, then set the reel using the procedure in the about paragraph.

Still not good enough? Now you need to have the reel and bedknife professionally sharpened. A reel sharpener is basically a lathe with a power grinding wheel on the tool post, traversing back and forth. After a shop grinds the reel, they will then backlap reel & knife to clean up the last few thou, and then set the reel using the paper strip method. Figure $75 for a backlapping and $125 to $150 for a full sharpening.

As for cutting height, you said you were already at highest in front. This means you have already pulled out the cross rod for the front wheels and placed the rod in the lowest of the three holes in the sideframes? As for the rear wheels, adjustment is similar, but much more time consume. It's been my experience that usually adjustment of the rear wheel high is rarely require, as long as you are already in the middle position. BTW, for years McLane had no rear wheel adjustment. The rear mainshaft (which the wheels rode on) had its bearings pressed directly in the sideframes.

Is their a way to adjust the height of handle bars? I'm 6.5 and it's hard on my back.