renegotiating lease in caribbean

Hi there,
I was given a parcel of land by my father a few years back. He had entered into a 10 yr lease with the major phone co. here in the island in 2003 for a cell phone tower on said land.
Since then, my father has passed and the land is now under my management/ownership and I have built a home behind the cell phone tower (perhaps about 250 yards away) - it was the best spot.
I am having difficulty wording a letter requesting a raise in the lease arrangement and don't necessarily want to go the legal route. What really changes the situation is (a) the proximity of my house to the tower and issue of land undergoing change of use by me, the owner (b) fact that the current value of the dollar does considerably less than it did in 2003 and (c) the fact that the phone co. were supposed to send me a renewal 6 months before the termination of the lease i.e 6 months prior to Jan 10th, 2013 and they have not uttered a word.
Not sure of what my approach should be but I would like a considerable raise in rent.