Clutch Bleeding nipple size

[scotstern]

OK, I screwed up. I finally found the bleeding nipple and I tried to loosen it with a 8M deep socket and an extension. First I was able to do so and then I could not get the socket off of the nipple. I tried everything so finally, I jest took out the nipple and you guessed it, it fell into the abyss known as the engine compartment. I have been searching but to no avail. Does anyone know the size or a part number so that I can order a new one. Now I have a real mess! Is this a part that I can get from a regular auto parts store?

Thanks,
Scot
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