Tommy,
Two things you might consider adding:
Hitting a heavy bag, if you have one available, just three 3 minute rds. Two or three times a week. You'll be shocked at what punching does to your body!
Think about the body of any good boxer.
Also, for the last month throw in halo.
I made the decision at 50 to be in the shape of my life, and just kept going until at 54, I was the oldest guy in the state to fight in a Tough Man contest.
It can be done! Good Luck! Enjoy!
(PS: Yeah, I won, against a 25 yr old who was also heavier than me. TKO in the first round. I think he kinda overlooked The Old Man.)