Thank you as well. I've been wanting to write up a "How I did it" when I get more time to help anyone out who is thinking of doing the same, and lessons learned by.
To answer your question though, It turned out to a roughly a 2"x 6" area of facia removed from each corner. The trick is to remove enough to allow the corners of the grill to "seat" but yet not too much where it looks like a chainsaw was used.
I've seen a few variations of 1500 bumper facias, so not sure if the same would be needed for all, but this is what was needed for what I have. I cant see how it would be drastically different though. (Proceed at your own discretion). As mentioned in a previous post, "start small and gradually remove more material as needed. I'm sure there are other ways to accomplish this, but I found that a Dremel was my best friend.
Here's a few rough pics to give you and idea during the process.
I'll be glad to help if you or anyone has any questions etc.
Note also I needed to trim the Grill bottom attachment point as the 2500's are not lined up the same. I could have removed it from the grill, but really didn't want to Frankenstein it. It was a good path to go.
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Transposing the area to trim to the right side. A "China Marker" comes in helpful.
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The aftermath. Top is whats left of the right side as I took constant cuts & grinds. Bottom is the left side once I had a pattern to follow.
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