Just wondering if anyone has any info on putting a newer straight 6 in a 1966 mustang or if its even possible. My brother and I are working on his 66 and just the other day he lost compression on cylinder 4, after scoping the cylinder i saw a hole in the piston so its time for a swap. He is not interested in a v8 swap so we are sticking to the 6. He is waiting on his new bronco so trying to keep costs down for now so hes waiting to sink in the money for a full rebuild so we are looking to throw a used yard straight 6 into the mustang for now. I'm not sure if the block stayed the same in the newer i6 or if it was just a head change. I was wondering if a newer block with his 66 head would be a possible solution.