Technical 38 CHEVY TRUCK DASH QUESTION HELP NEEDED

im about readt to mount my gauges to my 38 chevy truck dash.they bolt in from the back of the dasu.there are studs welded/braised to the dash.anyone know what thread they are.they measure 4.2 mm approx.less than 3/16 I think.5/32 maybe.these size nuts are not falling off the shelves over here,everything is metric.thanx in advance for your expert help

 

4.2 mm = .165 in. They should be a #8-32.

 

I have a tap that is comfortable through a nut that fits well.hard to read it.either #8-32 or #6-32..i reckon you are right thanx bud for the help

 

6-32 is .138 inch or 3.5 mm so I'd say it is 8-32.
Tom

 

I have a spare 37 Chevy Truck dash from one of my old parts trucks which is the same as a 38. Just checked the studs and they were definitely 8-32.

 

8-32 it is then ,thanks

 

ooP's slow to the answer but my 38 Panel truck is ALSO 8-32.
Old picture (brother)from 1965 . As you can see it was a beer delivery truck.

 

Driving it around making improvements.
.

 

rare truck id say,nice

 

^thanks , Had to cut down 4 trees (growing out from under it) to drag it out, only paid 20bucks. Ya back in 1964, trees were (thank God) only 16 years old.

 

knowing I had the correct thread I drilled out some m4 nuts to 3.3mm and ran the #8-32 through.m4 stainless washers are a good fit ,lockwashers too.made a few calls #8-32 bolts not readily available,so made my own stainless ones bolted the 3 gauges in for the first time like it[/ATTACH]

 

I rubber mounted the dash using 1.5 mm rubber tape ..drilled the mounting either side andmade an earthing point either side.will earth the dash either side