Neal’s is only about 3 miles from my house. I looked there when I was bus shopping a few years ago. I still stop by there when I'm driving by and see what they have. I bought my "new" drivers seat there too. Anyway...
I have a 91 bluebird and I found my axle ratio stamped on a tag inside the bus by the front door. There was the engine serial number, and a bunch of other useful info on the tag as well.
As for adjusting the governor, I didn’t do mine but I watched Jason do it. On mine all he had to do was unscrew a cover and turn the spring in a few turns, then adjust the idle. It's going to be different depending on what injection pump you have. Maybe post a pic of your injection pump and someone on here can tell you how to adjust the governor.
Here is a link to a post about adjusting the governor
http://www.skoolie.net/forum/viewtopic. ... light=tach
Here is a post I started last summer when I was looking to add a tachometer to my bus
http://www.skoolie.net/forum/viewtopic. ... highlight=
I never did it; I ended up using a rear end gear ratio calculator to get my RPM's at a given speed. Heres a good one.