70 w31 olds

[will]

looking for info on one of these,
a customer of mine came in today, (he knows i am in to cars)
he has a supposed to be 70 W31 old f-85 club coupe ???
he like to sell but isn't sure what to ask. things are a little tight so he's decided to let it go.
he has the POP and the block matches, he's the thrid owner.
it's an auto, 3.91 posi. I haven't seen the car it self but pic's look like a nice 20 foot. heads are 71's and has after market intake and headers. he has a folder full of info including previous owners, 2nd owner raced the car. has 80k plus showing on the odometer.

any info would be great, like what and where numbers are, what it could bring if it checks out.

I'am going to get some pic's tonight, get this it's sitting in a barn !

Will
what do I need to sell this car for him