Are 510's more desirable than a Z, this is not the first  time I see crazy money on the Z little brother >>> http://www.ebay.com/itm/Datsun-Other-2-door-SR20det-1971-datsun-510-2-door-sr-20-det-/141461637497?forcerrptr=true&hash=item20efc54979&item=141461637497&pt=US_Cars_Trucks

Surprised someone offered that much with the salvage title. I know with classics it isn't that much of a big deal. I think that the price is just because they are more rare. Even the junk 510s are over 4k where I live. 

There is no doubt the dime is a cult car and buildable to the teeth. I have people wanting to buy my wagon all the time.