[Kenny Wigington]

I'm guessing you have drum brakes on rear ? You can measure the brake drum size and some careful measuring might get you some larger brakes , like from a truck or van. Buying 2 sets of shoes and installing the long ones only will help some, it's old bracket racing stuff. A band aid, if you will, but if you are serious, get disc's for the rear. It will make a big difference.
Personally, I use a brake pressure gauge, to know where it leaves best at, consistently. Some dont like them, but, it does for me.