Only Connect #71 Mystery Cache

Number 71 of the Only Connect series of puzzle caches. Well, would you know it but the published coordinates are not where you will find the cache. Solve the puzzle to find them and they lead to a magnetic BYOP final. The cache itself can be found at an appropriate final location, where you will need to take severe care as it is beside a very busy road. There is room for a car to park very close by.

The rest of the series can be found by clicking on this link to the Only Connect bookmark list.

You are looking for one word which connects all five images. Please note that of the image answers, A-D are one word each and E is made up of two words.

F=the total word value of the one word associated with A (A=1 ... Z=26).

G=the total word value of .... B.

H=the total word value of .... C.

I=the total word value of .... D.

J=the total word value of .... E.

K=the total word value of the singular noun that connects them.

The cache can be found at : N55 00.Y W002 21.Z

Where Y = J + H + ((G + I) / (F + K)) and Z = (H * F) + I - (J * K) - G

You can validate your puzzle solution with certitude.