piston questions

Ahhh... Fark ... You guys are dragging the story of the failed rebuild out of me .. but that was only one of 3 things that happened while putting this thing together. And embarrassing at that.
After I pulled the heads and replaced them with the EQs I discovered my first mistake. I corrected that before I made the same mistake again.
Then once I got it in and running it sounded great at first. But as it warmed up it started running like crap. I shut it down, let it cool, and started it again the next day, would barely start, wouldn't idle without keeping my foot on it, and decided to try to take it for a short ride in the country and made it about 3 miles, it stalled, I had to call the kid with his truck and a tow strap to get me back home that 3 miles, parked it and left it sit about 3 years.
While I was sitting waiting for him I noticed that my brand new cat was glowing bright red. Melted, and the reason I couldn't even get it to run again. This truck the motor is going into now, ain't gettin' a cat.