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 >
>> > 
>> > Are there any other cars out there where there were two
>> > practically identical versions, i.e. Tiger/Alpine, but
>> > where one pulls in a much higher price?  And, how do those
>> > owners prove authenticity?
>> 
These are cars which could use the base version for parts or the
base version could be upgraded.
This has been done a lot on Mustangs to upgrade to GT350's.
 
 GTO- LeMans
Malibu- SS396
Satillite- Road Runner - GTX
Mustang- Boss 302, Boss 429, Shelby GT350,Cobra Jets
Camaro- Z/28
Firebird- Trans Am
Impala- SS427
Corvair Monza- Corsa turbo
Porsche 912- 911
914- 914/6
Vega- Cosworth Vega
Pinto- ????
Torino- Talledega 
Charger- Daytona Charger
Corvette- L88 
Buick-GS455
Cortina- Lotus Cortina
Omni- Omni GLH Turbo
mBrad
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