71 340 Challenger Value?

[71_340Challenger]

Money has recently gotten very tight and I am having to consider selling my 71 Challenger. The specifics are:
71 Challenger Coupe
Have original, #'4 matching 340/727 tranny, but both need to be rebuilt
Rebuilt and installed a 440/727 from a 76 New Yorker
   *Block, crank, heads cleaned, magfluxed and in good condition
   *New pistons ~8.8:1 CR
   *New bearings
   *Resused stock cast crank and rods, but put used ARP bolts
   *Aluminum water pump and housing
   *Edelbrock RPM manifold with 750 Speed Demon carb
   *Comp Cams XE274H cam kit with new springs, timing set, hydraulic lifters, pushrods
   *New mechanical fuel pump
   *Re-cored stock radiator with an additional core and higher densith of cooling tubes
Interior is in good condition, no rips, but not original front bucket seats
Column shift automatic
Stock 8 3/4 rear that has had the center section changed froma 741 to a 742 case with a powertrax unit
Piant is OK. It looks good from 20 feet, but there are a lot of flaws
There is a tiny bit of rust starting to bubble through on the passenger side lower portion of the fender, right near the door. Otherwise, the car appears to be rust free.
All new stock brakes (rotors, caliperss, drums as well as pads)
Electronic ignition conversion with orange box
It is a non A/C car.
It is in good running condition as well.

I am attaching a few pics as well. I will get some pics with the 440 installed tonight. I was curious what people thinks its value might be.  Thanks in advance. I really am hoping not to have to sell it, but just in case I would like to get an idea. Just for information, I paid $8200 for the car about 2 and a half years ago and have since put $4000 into it between the motor, tranny, brakes, and stuff to keep it running.

[71_340Challenger]

A few interior pics

[71_340Challenger]

A few other pics that might be helpful.

[71_340Challenger]

Here are a couple of pictures of the nwe 440 installed with new Schumacher headers.

[Rev-It-Up]

I'll throw out a number to get the ball rolling...  I'll say, $15K to $17.5K.

[mmccarty]

  My first thought was $15k or so. 

[71_340Challenger]

My initial thoughts were in the $15k-$20k range as well. But, you always think your own car is worth more I think. And, looking at eBay, and all the auctions, you start to think your car is worth a lot more than it really is. I really don't want to have to sell it, but if things don't work out, it will probably have to go.