What is a "Hurst 340"? Craigslist ad...

Thats just it... he put all this time and effort into this "custom" rear end, but keeps the 8 1/4? Not that theirs anything wrong with that, but??

I noticed that too, "hp plugs". What is that?
the HP plugs were unique to the Hurst built 340's and were standard equipment. they have adjustable heat ranges.