Don't you love that bigass radiator? Some guys wish they could fit such a huge area unit in their vehicles. Try to route as much air flowing to it as you can(avoid a skid plate that blocks the hole bottom half).
You'll be making skids plates and bumper pieces, get those powder coated, and maybe make a few splash guards to lessen what gets to the floor pan etc. I'd clean the bottom side really well though, and then coat it really well to seal the seams etc. Here's the bottom of my 99, I rust treatment coated it and ended with 3M rubberized under coating. I'll do almost the same thing with my 98, it saves the body for decades.
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