Re: i weigh 277
Just go with prolly a 48 or 56 for good results. Maybe even a 60 or more if it's real hilly. You will just have a slower top speed and cruise speed and gas milage.
Very much worth doing. Any mbike geared for off road use would prolly suit you well.
There is a gear calculator in the DIY forum that may help you decide about gearing. For the HT engines I think you have to enter 4 to 1 ratio for first gearset on the chart.
Do it, and you will have more fun than you know :~)