Because I just replaced my 2.41 peg leg rear end with a 3.73 posi my speedometer was reading quite a bit off. Instead of trying to monkey with the transmission speedo gears I decided to go with a speedometer ratio adaptor.

I recently purchased a ratio adaptor from Rick at United Speedometer Service in Riverside CA. ( 800-877-4798 ). I first did a test to determine how far off my speedo was by driving ten mile markers on the highway and seeing what the odometer read afterward. It read 14.3 miles. I gave this information to Rick and he determined that I needed a custom adaptor with a .6944 ratio. When I ordered it Rick said he would build and ship it the following day. A week later it arrived via FedEx Ground. It's installed now and works great.

I highly recommend them.

I too have used United in the past, in fact, I beleave I have even refered to them in several past Posts. Their New Shop is a site to see, Outstanding in every aspect.
They are known to take that Extra Step, and go the Extra Mile for their Customers.