'68 to '74 Replacement Fuel Meter Sending Units

[Floyd B.]

My fuel gauge is no longer trustworthy. It reads well past full most of the time, until the fuel level gets down to about a 1/4 tank, then the gauge drops down to almost empty. I suspect its the sending unit, but I don't want to start disassembly and repair until I start the full restoration of the car in a few years. I notice there are still some NOS units available but they are very pricey, so I'm trying to decide if I should grab one of these units while they are still available. I see my options as:

• Buy one of the expensive NOS units and put it on the shelf until I'm ready
• Buy a good quality service replacement to be cannibalized for parts to restore my original
• Buy a service replacement and take the hit on points (i.e. no "AC Made in USA" and a few other details)

If I choose not to buy a NOS unit, I need some help choosing a replacement. There are at least three historical part numbers for the '68 to '74 sending unit:

• AIM has 6428127
• Circa '74 Chevrolet parts catalog has 6428164 (this is the most common NOS number used)
• At some point (late 90's?) 6428164 was superseded by 19180449

There are various repops (probably Chinese) sold by suppliers like Supra and Dorman. I'm not interested in these. It appears Delco/GM has discontinued all versions of this unit.

Has anyone installed one of the later AC Delco service replacements - either 6428164 or 19180449?

I see Dr. Rebuild sells a replacement unit described as, "Delco Repro of GM 6428164." Has anyone installed one of these?

Thanx

Floyd