Sell or keep

I would like a little advice on which way to proceed and couldn't think of a better place to ask. I've posted a few pics of our 1973 "Demonized" Dart Sport earlier in the year and have put some money into it (app 7000) with a purchase price of 8,900 and are debating on investing further or selling and buying a true 72' Demon or something similar. We bought it just last May 2012, it is a 1973 Dodge Dart Sport but is badged with Demon emblems by the prior owner. Painted hemi Orange in the 80's original paint code is buff (beige'ish) had a 340 but now has a mildly built 318 with a 727 trans. We had a plaque designed with a modified Demon logo placing a halo above the Demon with a quote beneath stating "With God it's never too late" using it as a mission tool of sorts. Already replaced tie rods ,ends, brakes, rotors, wheels, tires , originally had MT 50's on the back with a narrowed rear end and they widened the rear wheel wells to accommodate. New ceramic coated chrome long headers and custom exhaust. Interior is excellent and I added some black carbon fiber dash and console inlays. No rust as it was restored in the early 90's I'm guessing but getting a few bubbles in the paint in front of the back wheel wells and are hem hawing at getting another restore and new paint estimated at 6,000. We are now at the dilemma of putting more money into something that isn't numbers matching and a true Demon. We know we'll never get back out what we have into it, but we are thinking of selling and buying a true 72 demon. Any thoughts or opinions? all would be welcomed.