Another check might be price?
A Real Original >
$500,000, consult an expert to avoid a huge mistake.
A real glass CSX should be $75-95k depending on options. If is ally body it will be >$100k. If the car is less than $50k, you will need to do a further check of what it is.
Shelby fast check for the novice:
1) Footpedals should pop out from underneath footbox like this:
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2) Look under car, if the frame is not round, like this, it is a kit of some sort.
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3) If frame is round, look at hood underside, should have a 1/2" tube running around the underside edge like this. If not, you need help as it is a kit....
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4) Look under at the rear end, if it is not an IRS similar to this it is a kit.
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5) Look at the rear leg of the roll bar should be ~45 degree pitch and enter trunk at least 2/3 of the way back towards trunk hatch.
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6) Wheels, they would be single nut pin drive. If you see a lugnut on the wheel it is a kit of sorts.
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7) If the man selling the car looks like this, ask for his signature, if he charges you for it - might be Carroll himself:
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MOST important
do your homework......