Here are some exercises to improve your mobility.
The Bench Bar is for those who have restricted shoulder mobility.
Kneel in front of a bench and place your arms on it., Palms up with your elbows centered in the middle of the bench. Using a bar or single dumbbell sit back on your heels bring the dumbbell or bar over your head and lower the weight behind your neck., Place it on your shoulders forcing your neck down. Down three of these.
The Foam Roller T-Spine overhead stretch. Stretch out with your hands over your head, Then slowly bring them down with the back of your hands towards the floor in a 90-degree crucifix position. Raise and lower your arms to increase the stretch and three sets are the minimum to do. To increase the stretch place a roller under your back for support and intensify the exercise.