you need to make the algebra work
Cache is at N51 3T.ROU W000 1U.BLE
the boring bits... the puzzle requires a series of logical algebraic deductions but instead of finding numbers on a church noticeboard, you have to do the arithmetic from scratch, no digit is assigned to multiple letters, letter O does not equal number 0. Each letter keeps the same numerical value throughout. suggested parking at the posted coords. GZ is a quiet residential area where they don't necessarily take kindly to witches brewing potions, so discretion please, you are not directly overlooked. There is likely to be nobody around but please avoid being seen. It is a public road, inhabited by nosey parkers. at GZ you will see a low signpost which confirms this. then it's behind you. Cache is large tupperware, big enough to notice with the naked eye in the obvious place in undergrowth.