Fitting Speedhut Gauges into Datsun Z

Product Arrives

I ordered black dial, red numbers, red glow, Datsun Z numbers and ticks: Datsun Z, red-glow pointer, stealth black bezel.
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Gauges arrived very nicely packaged.

Stock Gauge Disassembly

Remove the four screws that hold the black plastic bezel to the metal can.  Save the screws.

Pull apart the bezel components. Set aside the clear plastic window, it will not be used.

Remove the pointer and dial face.

From the back, remove all the nuts and screws.

Set all parts aside (except the metal can), they will not be re-used.

Use a sharp craft knife to remove the heat-staked green gauge illumination lenses, 4 places (red arrows).

Drill-out the four spot welds (yellow arrows).

Note: This will be a slightly different layout for the speedometer.

Green blinker lenses and ‘tube thingies’ removed.

Green gauge illumination lenses and blinker ‘light guide tubes’ removed.

Modifying the Metal Can

The assembly will go back together in this order.

The thickness of the SpeedHut Gauge bezel will require shortening of the metal can.

There is a small, triangular nub that will prevent the bezel face from sitting flat against the inside of Datsun bezel.

Use a sharp craft knife or flush-cut cutters to remove it.

(Sorry it is difficult to photograph black-on-black).

Pinch everything together. Confirm the gauge is centered and fitting flat against the Datsun bezel.

Use a sharp, pointed tool (I used an Xacto knife) and scribe around the perimeter of the Datsun bezel

I used Dykem Layout Fluid to make the scribe marks MUCH more visible.

I made a makeshift grinder setup and carefully shimmed the metal can until the cut line was exactly right.

NOTE: I originally tried to cut the metal can on my bandsaw. I DO NOT RECOMMEND.

I carefully rotated the metal can, removing just a little material with each pass.

Patience is essential at this point.

This ‘technique’ worked perfectly, safety notwithstanding.

Modify the plastic gauge retaining ‘nut’

Modify the Plastic Gauge Retaining Ring

I used a drum sander in my drill press along with a jig to remove just a little plastic around the entire perimeter of the retaining ring.

Remove just a little material at a time, evenly around the entire circumference, and test until it slides snugly into the metal can.

When a nice fit is obtained, screw the retaining ring onto the gauge and snug-it-up against the back of the Speedhut bezel.

(Place a grommet in one or more of the holes through which the wires will exit the metal can.  I used grommets for a 9/16″ hole.

Thread the wires through the grommet.

Slide the gauge into the metal can.

Replace the four original screws (you will most likely need to shorten them).

You want the screws to press into, but not deform, the plastic retaining ring to be sure it doesn’t slide or rotate.

The OUTSTANDING results.

This gauge has the identical dimensions and will use the same mounting method as the stock Datsun Gauge.