We live in Tucson and would be honored if we could get into Mayo in PHX.
Anyway...... what has helped?
Stress reduction and stimulus reduction both reduce the tremors. What might be happening is an overloading of nerve signals in the brain stem where all these signals get bottle necked and the body responds is tremors.
Here is an example of how I know stress aggravates the tremors. Wynne's tremors have been getting better over the last few months along with her overall health, which is still very bad. The past few days Wynne has been having more nightmares and wakes up stressed about these nightmare that seem real to her. Also the last few day her day tremors have come back some and her night internal vibrations are more along with her muscles jerks.

Here is a short answer to your question about what treatments help
*LDN
*Antihistamines
* Both stress and stimulus reduction
* Pacing
* Propranolol may or may not be helping