Bubble-top was an option, a long long time ago.
GM stopped making 427's back in the early 70's, who in their right mind would think one of these cars would come out with an engine they'd stopped making at least a decade before your body style was even designed? And 454's? Hmmm maybe some special cop editions had them, but no stock civilian Caprice came out with a 454. The 427 and 454 aren't even the same generation big block, having them in the same car only happened in the transition year. 1972 iirc.
Only someone who has never been around cars/engines would believe a stock 350 with a rebuilt carb is hitting anywhere near 400hp, let alone 500.
I rented a Caprice back in the late 90's that had a 305 in it. While that engine is generally JUNK, I was impressed how quick the car was. It was comparable to me big-blocked cadillac of the time. But even with that, the numbers stated in this thread to bolster Caprice support are just beyond ridiculous. 427's and 454's in them? Stock small blocks making 4-500hp? 4-speeds? lawl Give us some credit for having brains, that shit wont fly here like it does with your local boyz.