I want to shoot in the 80s without pain

There may be many factors preventing you from shooting in the 80s but pain should NOT be one of them. Common conditions which may affect your golf game include:

Golfer’s elbow (medial epicondylitis)

Tennis elbow (lateral epicondylitis)

Low back pain

Hip osteoarthritis

Knee osteoarthritis

Rotator cuff strain or tear

Wrist ligament injury

There may be certain aspects of your swing contributing to the pain or causing more pain. For instance, if you have pain in your lead hip with your follow through you may have a lack of internal rotation. 

In conditions like osteoarthritis, torsional compression during follow through can cause pain. Something you may want to try is opening up your stance (point your lead toes more towards the target) thereby placing less stress and internal rotation demand in your hip.

Tennis elbow is another injury more common to golfers than you may think. If you are experiencing elbow pain it may be due to chicken winging, casting or sudden increase in volume of play. Something to consider with elbow pain while playing golf is modifying the swing. You may be coming over the top. Talking to your golf professional about altering your swing path may decrease stress on the elbow. If this does