Here are some pix showing the factory shroud next to the new one. Note that the factory shroud is wider to fit the wider, high capacity radiator. Also note the difference in the bead-rolled edge compared to the factory flat edge.
The factory shroud mounted to a standard radiator has been in my truck for a couple years. I cut the brackets off one of the high capacity radiators that was shot beyond repair and use them to mount the factory shroud. I included pictures to show how the brackets are angled to make up for the forward lean of the core support, and also to show the factory shroud mounting tabs.
Also included is a close-up of one of the side brackets for the new shroud to show the multiple breaks necessary to fit over the radiator bracket. The pieces are more intricate than they first appear.
Why are we going through this effort, especially since 235's and 261's are typically cool running engines? Adding AC can cause cooling problems, particularly here in the Arizona desert. And it's not just an engine cooling issue because it takes increased air flow for the condenser to work properly. There are different fixes including six blade fans and electric secondary fans, but a shroud should improve the performance of the stock four blade fan to handle both AC requirements.
