Help with a treasure hunt and some COGO terms

[navdog]

This may seem like an odd request, but I am looking for a geocache and need to do some type of coordinate geometry using terms I know nothing about. Here is the text of my quest, if anyone could describe this in laymen terms it would be great! I'm mostly confused about "inverse headings and distances" and the term "AR". Thanks for any input.
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The above coordinates will place you at a convenient place to park while doing this cache.

1) Traverse in an Easterly direction to the first power transmission tower and stand at the Southwest corner to start the math, calling this MP1 (your decision as to the necessary math required to get to the cache).

2) Traverse in a Southerly direction to the next power transmission tower using the Northwest corner as your 2nd math point calling this MP2.

3) Traverse to the 3rd math point by... BS Northern power transmission tower, AR 360 minus Inverse plus 22 calling this MP3.

AT MP3 add up all Inverse Headings and call that calculation (TH). Add up all Inverse Distances and call that calculation (TD).

Now to the cache from MP3.....

4) BS Southern power transmission tower, AR TH minus 760, and traverse a distance of TD minus 2500.

The above calculations, based on your 'COGO with a GPS', will place you well within a five foot circle of the hidden but still visible small cache, 3/4”dia. x 2-7/8”long tube (see picture), hidden in the most unusual way (not buried, just well concealed), that contains a pencil with a rolled up log sheet around it for logging your find.

 

[sc]

Sounds like an exam question

 

[vicman2]

AR stands for angle to the right from your backsight (BS) or previous traverse station.

 

[pecosjack]

The inverse they refer to is the azimuth and distance from the occupied point to the BS point, also know as the Back Azimuth. It would probably help if you drew a sketch of the traverse as you went and match it to the directions.