Which radiator for 2004 GMC Yukon VIN code U

[oldchev]

My 2004 GMC Yukon Denali AWD 6.0 needs a radiator due to EOC line output leaking at radiator. This is the internal seal. Rather than attempt opening the tank end to repair I am going for replacement AC Delco unit. The issue is the are two numbers than the VIN code (U) represent, GM22840116 or 21649 has a core unit measurement of 34 x 17 1/4 x 1 1/8. The other is GM22840117 or 21653 which has core measurement of 34 x 18 1/2 x 1 1/8. Depending on how you measure in the vehicle which is hard to get to it appears either would fit. Logic says get the biggest one that fits, right?
Anyone have experience with these AC Delco numbers? Which is the best or either? They can be found online at various vendors including the popular one.

 

[El Capitan]

When mine went out I replaced it with the larger of the 2 I didn't pay attention to what I had prior but I have not issues as of now.