blowed up slant 6

Here's a picture of the engine block. I wasn't really Rodding it. I had just got up to highway speed when it blew. My guess is it spun a bearing. when I got the oil pan off there was about a half pound of metal shavings and hcunks of the piston floating around. I have a 360 I pulled from a van that I would like to put in it but I'm still looking for an 8 3/4. I also have a mystery Engine I picked up from a buddy.not sure what it is but its a mopar. I just put in another slant 6 from a 72 demon with 26,000 miles on the clock. still don't have it running yet though. this is the first time I've ever turned a wrench so it may take awhile.........

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