Radiator conversion

[Smiling lemon]

I'm down in Tennessee, I don't have a major or leak but it is a drip coming, I have heard about the dimpling, how many cores are the most efficient? I have seen 5 cores and they seem to have the dimpling but I talked to a guy before(he may not know what he was talking about) That had a 5 core and when he put a 4 core in it, it cooled much better.