Here's my first letterbox clues. I did it as a rhyme.

The azimuths are true north and the paces are 2 steps. The magnetic
declination here is 11-1/2 degrees west. So add 11.5 to all of my
azimuths.

The starting point should be easy to find with some short historical
research. Most people in my section of the state would know as soon
as they read this. We're expecting rain tonight and I'm going to go
back next week to see how it weathered. As an added incentive to get
this thing rolling, I'm thinking about placing a gift certificate for
a free meal at a local restaurant in the box when I go to check it.
The first person to find it gets the meal.

So here's the clues:

Stone Needle in New Jersey

In the state I am in, how high can you go?
The answer to that question Mr. Kuser did know.

He knew it quite well, but now he is gone.
And in the stone needle the answer lives on.

For the ultimate sacrifice it points to the sky.
So show some reverence as you draw nigh.

So find the stone needle and stand way below.
Where you pay to see far is the first place you should go.

Stand between those devices and admire the view.
You'll know you're all right if the stone needle is 219 true.

Now to the Needle take those devices and point them.
Add the numbers on their dials to 267 to go then.

Walk thirty-eight paces crossing drive and guide rail.
To a tree white as snow on the course of a trail.

Now thirty-seven is the way you should face.
And 109 double steps is the length you should pace.

You'll come to a place where you can't travel by wheel.
And look for the entry of the very same trail.

There standing before you is a pipe colored white.