I dont know if you make videos or not but i would be very very interested to see how you rehabbed yourself.
I have similar deficits/injuries and i am working torwards rehab, but its difficult when done solo, with no formal exercise science knowledge.
I have identified how much posture plays a role, and i know i tend to have forward head posture, and my one shoulder is externally/posteriorly rotated.
I'm working on it but I'd love to see how you did it!
Thanks!
I basically study the ABC's of physical therapy and personal training and corrective exercise selection, release and stretching techniques, joint mobility techniques, muscle length testing, etc.
A lot of work is involved in diagnosis , then exercise selection, then re testing, etc.
I think PT now is more advanced than it's ever been, namely because of the internet and the worldwide access to all the best doctors and the progressive technology and techniques has compounded the effort to a level to where it's never been better.
I can only point out some very good books/material that I have read and found very helpful that I would recommend to anybody wether or not they workout.
If you are interested in learning how to cue for proper posture I highly recommend picking up "Becoming a Supple Leopard " by Dr Starrett also "Deskbound" is another great book, also Dr Brent Brookbush has some great material readily available on an academic level.
Since studying and becoming so interested in the field I find myself always not only analyzing my own, but also analyzing other people's posture, not to be critical and not vocal but just for my own interest. FHP is super common with today's regressive lifestyles. I notice a lot of youngsters even teens with FHP and "Upper Cross Syndrome" . The world is progressively going lazy and the body is adapting to it and breaking down.
When I fixed my FHP I studied the muscle group responsible for neck curvature, and that group is commonly known as the "deep cervical flexors". In FHP this muscle group has a tendency to become weak and under active.
(When a muscle becomes weak and under active, the body recruits other muscles to complete a movement.)
In FHP the neck is usually in extension / the opposite of flexion, and, the neck extensors get tight and over active and become dominant in all the neck movement patterns. So the deep cervical flexors begin to turn off or become phasic , while the neck extensors become overactive or hypertonic.
To reverse/cure/improve conditions caused by muscle imbalances like that, one addresses and isolates the weak inactive muscle group to recruit it once again or wake it up,
or exercise that muscle and strengthen it to get it to become active again. The more it is exercised the more it becomes active. It is not just developing the muscle, it is also training the bodies neural response to fire into and recruit that muscle again. It's a retraining process to get that muscle to wake up and become active in the movement patterns again.
All the while when retraining and strengthening the weak muscles, the tight and overactive muscles can be released and lengthened to get them to tone down. Massaging or self administered myo-fascia release on select trigger points can cause an overactive muscle to calm down , also stretching the over active muscle gets it to calm down .
I can write about it but it is something that is very hard to do without doing testing and getting feedback, and demonstrating.
Always doing an exercise in as perfect as possible stance, cueing properly for good posture,
2nd toe forward
standing straight ,feet shoulder width, glutes and abs slightly contracted, chest out, shoulders back and down, chin tucked,
ears in line with the shoulders, etc,
Learning where exactly your braced neutral spine is and how to cue your body into it is an important starting point when doing corrective exercises and stretches for deep cervical flexors.
After being in a good stance , during execution of deep cervical activation, an often left out cue that I found very helpful when doing the exercises, is tongue on the roof of the mouth.
Following tongue on the roof of the mouth cue , more actively engages the deep cervical flexors.
Also i've found that tongue on the roof of the mouth can assist in FHP by using the tongue as a lever to help assist the head back in retraction above the shoulders where it is supposed to be.
Do you have an exercise/stretch routine for FHP prescribed by a PT ?
You ever thinkabout getting the body you have always wanted? With all the great YouTube fitness videos available you can do it! You don't need a club membership, just the internet and a little space to do the exercises. 
