A partial answer to my own question.
See this paper:
- Fresh (not frozen) sections
- No Triton-X. Just BSA in PBS for blocking and staining.
- 48 hour room temperature incubation!
- Monoclonal GAD67 ab from MIllipore.
I already have frozen sections, so not sure what will happen, but I'm re-staining without Triton-X at room temp for 48 hours.