[DanEC]

I have a standard water hose nipple that has a nominal diameter of 5/8 inch on the exterior of the threads - but it might actually be sized as something else - I'm not sure. I'm going to take the nipple down to Sears this afternoon and try to match it up against a tap - see if I have any luck. And then if I can match it up I hope the tap notes the size of drill bit I will need.

UNF threads - huh? Well, I guess they generally have screwed into the standard NPT hose nipple manifold opening or there would be a whole cottage industry built up around re-tapping out Ford intake manifolds. I will visually compare the nipple to the sending unit threads and see how they match up. But yes, they are Smith gages.

Thanks