Dearrangement, neck, lateral shift

I am treating a patient with a posterolateral disc bulge (as confirmed by MRI). Symptoms include pain in the left shoulder and arm together with pins and needles (radial distribution). The patient has a noticeable lateral shift of the head on the shoulders to the right and I am unable to find appropriate exercises for them to practice at home to reduce this.
The patient is currently unable to go into extension due to increased pain.
Is anyone able to make recommendations for centralising the pain and the position?
Many thanks

? Work on the soft tissues on the right side that may be pulling the head towards it.
Although this may take away the support that the neck needs right now.

There may be nerve compression in the neck that is causing muscle weakness and pain. Have you prescribed pain medications, have they worked?

I'm not a PT, so my advice is based on experience only. Seems your patient has entered a 'protected neck' mode, with stiffness and muscular reactions which protect the neck from further aggravation during a 'flare up' phase. Exercise regimes can be counter-productive in such circumstances, because the neck is already in resistant mode. Primary goal should be to find ways to restore normal flexibility to neck, before considering any other readjustment methods. The only way I know to restore unstrained flexibilty is through sleeping posture techniques, particularly sleeping or napping in semi upright posture. 2 or 3 days/nights of such sleep regime changes can allow the neck to revert to its default flexibility, and it usually helps with easing any radiculopathy, or other referred issues as well. The patient can monitor their own progress, and record any beneficial changes as a guide for future use. The problem with exercise regimes is the uncertainty of whether they are beneficial or not, so....the less threatening the process, the better options for monitoring postural sleep adjustments which might be more beneficial. An easy way to advise this approach would be to suggest testing some semi-upright napping on a sofa, with good pillow support, for a few days, and ask the patient to record any changes to their symptoms. Any good outcomes will define the postural changes required in future instances. It usually takes a couple of days/nights for adjustments to take effect, and it may be uncomfortable at first, but once the symptoms start to ease, the whole process should get easier. Half the battle is usually gaining the patient's commitment, but, once achieved, they will feel empowered to explore further.