If your sure the numbers on the pink dosen't match the numbers on the engine, you have a few different options, and i'd tackle them in this order:
#1: Post the VIN from the pink (or if your not comfortable doing that, eMail it to me) so we can determine if the number on your pink slip is an engine number or a mfg tag serial number.
If your number is NEITHER, i've heard of some areas DMV assigning a unique number back in the day.. maybe thats what happened in your case, and the year was determined by the year this new number was assigned.
If thats the case, then there would probably be a seperate number stamped on your truck somewhere.
#1a: If the number on your title ends up being a valid engine serial or mfg tag serial for a '52 (and absolutely isnt the number on your engine) then proceed to step 2.
#2: Go back to the dude you bought this truck froms house and tell him whats up. He very well could have given you the wrong title. If the guy has vanished like the proverbial fart in the wind, proceed to step #3
#3: AD_Pickups suggestion sounds solid, except i'd think you'd at the very least need to know the guys NAME that left the truck in your yard "5 years ago". I'm sure the DMV is going to need the VIN on the truck, and if it's been reported stolen, you may end up on the wrong end of a reciving stolen property charge.
Putting a lien on property usually requires the applicant (you) signing a legal document saying that what you're saying is the truth. The truth is you didn't have that in your yard for 5 years, and you have no idea the origins of the truck. I can't imagine a lien can be put on property without some sort of notification being sent to the last registered owner of the vehicle.. if this guy pipes up and says, "Hey! That truck was stolen out of my yard 2 years ago!" you could end up with some charges filed against you. (fraud, theft by deception, stuff like that)
I'd call your local DMV and see what they say you should do in this situation.. if you decide to commit a crime for the sake of getting a title, make sure the juice is worth the squeeze.
