i took an autometer, small tach, couldnt remember what size, and put it directly into the dash.
took original gauge out and disconnected large white box going to boost gauge
cut clear plastic over gauge so its straight in between the oil and boost gauges.
kinda hacked and cut white plastic backing till gauge fit at an angle i wanted, and one of the two bolts on the back went through the factory mounting hole, the other side was cut to fit the gauge.
ran line and mounted back up, gauge fits right into the hole of the black backing and i soldiered the illumination wires to the board on the back of the cluster to make sure it made contact. Did have to cut backing alittle to clear new gauge.