Nope, it didn't happen, with or without a garantee. The 66 goat was quite a muscle car, but there were a lot of 64,65,66 and up factory superstocks that would blow the Goat's doors off and they didn't do a wheelies when ripping the goat a new ass. I know, I owned a 65 Goat and got my ass kicked many a time by a SS409, SS427, 2+2 421, 426, 410, etc. Superstocks ruled the stock factory cars, but muscle cars, were a bargain, providing a lot of bang for the buck. If I had it to do over again, I'd of bought a 425hp SS409. It wasn't even a close race between the 66 SS409 and a 66 Goat. I got shut down every time I tried the SS409. Like the 57 chevy, the goats are legendary and now have a tremendous resale value, but they got beat at almost every stop light and if stock, still do today. The only thing the 389 goats an 396 malibus shut down were pony cars. Superstocks were way out of thier league.
I now have a stock 2000 LS1 Trans am convertible with a 6 speed, and it will blow the doors off the stock tri-power goat any time any day of the week, It won't touch a stock 66 425hp 409 though. Just like in 1966, my poncho is still shut down by the superstockers.