Alkymst,
If you went to Hopkins and were in the neuro dept, Dr. John Griffin (the head of the dept) would surely have been interested in your pre-diabetic Dx, as his main thrust is that PN is.... (in the majority of cases-he says) ...
a leading factor in PN onset. It is part of his long-term, ongoing PN research.
I'm one of his patients, and I joke with him -saying, he'd wait 25 years for a patient to develop diabetes and then say "Ah-Hah!..... See....!!
I told you, you were pre-diabetic - and that was the cause of your PN" .

The B-12 info from Rose is invaluable. I take 1000-2000 methyl every day, sub-lingual. I've been taking it for almost 5 years now and truly believe that it has helped (along with Lyrica & Tramadol) my PN symptoms become more and more manageable.

If you need B6, be careful- the P-5-P enteric coated is your best bet.
I take it to help relieve my carpal tunnel symptoms and it seems to be helping, I've been able to put off surgery, and have only had one cortisone shot (in the wrist/carpal) per year, for the past 3 years. My CTS symptoms have not worsened, or progressed. It has not interfered with my PN meds nor has it exacerbated my PN, in any way.