yes, I have seen the single type, would work for the front plugs .... they just get used like a washer under a pan bolt, the wires get held tightly enough there's no real sag .... the complete set looks about right, except for the price!! don't worry about the year specs, most places will tell you there was no 283 available for 57 as it was only offered for light trucks late in the year
I might try to get a pic of mine tomorrow for ya - if it stops pouring rain
and I'll see if I have any xtras
Bill
