G'day you blokes.
Yep....I agree. The Cortina TD type tacho gauge cluster is a bolt in deal. The Tacho function has a "trim pot" so all you have to do is turn it one way or the other to calibrate it against a known good tacho. Simple as that.

The only problem I found with the Cortina Gauge cluster is some of the warning lights don't match the original F100-350 cluster. Also you need to run an extra wire for the tacho. Don't forget to use the Cortina type Oil Pressure sensor as the regular Ford F series type didn't work in our '75 F100.

Cheers.........Barry.