Gauges 1966 temp/gas part missing

Here's something to consider concerning the inoperable tach. The tach on my 66 was inoperable when I got it. Turns out the sending unit and the tach electronics were fine. The problem was a sticking gauge needle/hand. The hand can be adjusted to relieve the bearing pressure. I added a miniscule
amount of clock oil and it's been working ever since. While the instrument cluster is out, add a drop or two of oil to the speedometer bearing housing where the speedometer cable screws onto the housing. (there is a small oil port for oiling)