I did not know this, and upon measuring mine, its only an 18 inch core. regardless i'll be making one of the larger ones fit. Thanks for the contributions.
Adding a larger radiator is pretty simple. With the 18” cores I believe the opening in the radiator support is still 22”, I think there were only two different radiator support structures that were used. I’m not sure if the mounting points are the same as for the 22” radiators, but they might be. So a 22” radiator would be a pretty simple install.
With the 26” radiator the mounting locations are definitely different, so you have to drill the new holes in the radiator support for the bolts. When I installed my 26” radiator I actually welded the nuts to the radiator support similar to the factory mounts, just to make it easier to hang the radiator in there by myself. The opening in the radiator support is still 22” on my car too. You can trim the opening back, but it’s not mandatory. You’ll still get airflow over those outside tubes, just not quite as much. On my car the whole core is still covered by the fan shroud for my electric fans on the backside, so air still gets pulled across the whole surface with the fans running. At speed I’ve never had a problem with the temperature, so I never felt the need to open up the radiator support to the full 26”.
