302 to a 351 cleveland or modified?

hi everyone, I'm new to this forum so I apologize if these questions have been asked before.  Currently I have a 302 and a c4 tranny in my jeep, I'm picking up this weekend hopefully a 351 cleveland with a c6 and a 351 modified with a c6 behind it. My main question is will the motor mounts and tranny mount line up with the exhisting ones fromthe 302 and c4 tranny. I knw a 351windsor would but not sure about a cleveland or a modified. And I have no clue about the c4 to a c6 tranny bc I'm new to the auto trannys.  Does anyone knows if these will interchange? And also will headers line up on the heads from the windsors to clevelands or modifieds. Thanks in advance  

the 351m is considered a big block.EVERYTHING is different. clevelands, windsors,302's and 289's are smallblocks. a lot of this will interchage. in my opinion the 351m-400 was about the worst thing to ever come from FoMoCo