another gauges issue...

[NO_H2O]

I put a Summit A/F gauge in my son's bus. Most A/F gauges will work with stock narrow band O2 sensors. The diff. between a 1 and a 3 wire sensor is that the 3 wire sensor has a 12 volt heater and the 1 wire does not (takes a little longer to start working).
I have run VDO CHT gauges on most of my cars. I looked at an Autometer CHT gauge but most are 100-300 deg. max and the senders for the spark plugs are $90 ea. The VDO is 100-600 deg. and the replacement seners are $14.