ethics and laws.

[elcamino72]

From a legal standpoint just by selling a vehicle which has an engine which carries a restamped code, you are opening yourself to a possible lawsuit if you do not disclose it as it could be seen as a representation that the engine is original especially if the buyer relied upon the stamping when deciding whether or not to purchase the car. (Whether or not he asked if the stamping was legit is immaterial, the seller had a duty, if he could have even reasonably foreseen the possibility that someone would rely upon the stamping to decided either the pedigree of the car or whether or not to buy it, had to disclose the fact that it's been restamped)

While you may believe that it's "caveat emptor", the law is clearly slanted in favor of the buyer, it's much more so seller beware.