You are 69, have a Gleason 6 and are being given 3 months to make a treatment decision, correct? I have no idea what your resources are or where you are being teated but you may want to get a second opinion. There are considerations such as where on the prostate was the cancer found that influence a decision to urgently treat. Obviously you just can't ignore it, but with a Gleason 6 a month deadline may put you under artificial time pressure. Here's something from Mayo that touches that topic.
http://newsnetwork.mayoclinic.org/discussion/weekend-wellness-gleason-score-indicates-grade-of-prostate-cancer/
Treatment selection can be very stressful so extra information can be very helpful. My 2 cents.