No offence, but you (if you're the advertiser in Hemmings) did say it was numbers matching! Isn't the Hemmings advert just a wee bit misleading then, if the car doesn't have the correct engine & trans? First couple of lines copied direct from your advert below and underlined/bold, for reference...
1970 Mercury Cougar Eliminator Boss 302, Original Condition, unrestored, numbers matching, 20,263 original mile Boss 302 Cougar Eliminator.
Presence of a date correct block and/or trans, does NOT make a car numbers matching, just in case you're wondering. Your butt would be in Court faster than a Defence Attorney on heat, if you sold that to me pretending it was numbers matching (though I'd pick that a mile away myself, but some poor unsuspecting/trusting person may get shonked on that detail, which is pretty rude). It's further misleading, as it's not in original condition, if the engine and trans have been removed and replaced, no matter how accurate the dates on the replacement parts. It's like the old 'survivor' car story that's been half restored and all mechanicals rebuilt - ie: not a survivor. I'd like to see that Hemmings ad revised to be a little more truthful.
Nice looking car, though.