I've mounted a Mallory dial-adjustable rev-limiter tach directly in front of the rally dash tach, same diameter, attached to the upper plate of the inside dash (almost looks factory!). However, the smaller diameter steering wheel I have (11.5") does cross over the view of the tach, along without the crush plate (deep dish Superior-brand wheel), but you get used to it (possibly, a tilt column would relieve that issue). I've also occasionally had a small ~2.5" tach simply velcroed directly in my line-of-site on top of the dash.... for autocross and road course lapping, the direct eye-site of the tach is important... look at how the well-thought race cars place their tachs and other gauges. I would like to eventually make a complete custom dash with plenty of gauges (no need for a clock in the dash... takes up too much valuable space, as well as no need, for me, for a radio/stereo.. too much unnesssary weight (ousted years ago!)... gauges could fit there.. my music tunes come from the engine and the exhaust/Flowmasters!... ;<))