Stuck with stock 833 speedo gear with 3.91 rear gear?

TrailBeast said

Apparently Brewers Performance would have another opinion.
Towards the bottom of the page.
Brewer's Performance - Mopar A833 4-Speed Transmission and Component Specialists

Click to expand...

Just talked to someone there yesterday. That's who told me I was stuck with 18 or 20 tooth which would do nothing for "actual speed"ometer
with 3.91 gear and 26" tire.