Leveling Mower Deck

I put the mower deck in the lawn tractor yesterday and did the routine prep- checked tire inflation and leveled the mower deck. After mowing the lawn, I realized that I must have done one of the worst jobs leveling the deck I have ever done. I use a 3" length of rope to level the deck side to side as well as front to back according to the JD manual. It is always a PIA as the tip of the blade is above the outside cowling of the deck (as it should be) and is therefore invisible unless you are the height of a worm. Is there an easier way to level a mower deck?
Bonehead

I just eyeball it. Sometimes I give it a kick or run it into something in order to straighten it out one way or the other.

PB

At work, find a piece of level concrete (the longest part of the process), lay down infront and spy with your eye.
I got a mauual to show how to do it proper, try and get a shot of it, though you probs dont care

From the manual