My chest was similar to yours and I had my surgery 5 weeks ago at the age of 58. I think you're going to have a great outcome, as long as your surgeon has a good history of gyne surgeries.
I'm really happy. No problem with a lack of skin shrinkage. Now my chest matches the rest of my body. (Actually, my chest now is probably the best part.) The only visible hint of the surgery are the small incision scars. Although I still can feel hard areas of scar tissue under the skin, they're not visible to others. And I finally have my full range of motion back (it took 5 weeks).
My recommendation is to strictly follow your surgeon's instructions. Keep that compression garment on and don't worry about how you look in the first few weeks. It takes longer than you think (or want) for swelling to go down and for your body to adjust. I didn't return to the gym until week 5. I wore a special compression wrap for the first week, then a compression vest for weeks 2-4, and for the next month I wear an Under Armour compression T when I go to the gym (per my surgeon's instructions).
Best of luck and keep us posted! It is great to hear from "older" guys who are finally making the move.