I've tried twice and come up short- here's what NOT to do...
The first time, I tried cutting and pasting just the grille area from the Revell Escalade (after I'd cut the hood open) to the Silverado nose. That effort ended when I realized I'd still need to splice in the fender flares and rockers from the Escalade to the pickup, not to mention the repair work I'd need to do to the Escalade hood after my somewhat ham-fisted attempt at opening it.
On the second try (which didn't turn out totally unsalvagable, and I may finally finish it one day), I still opened the hood, but I cut off the Escalade front end at the front door cut line, and just above the rocker panel cladding. I essentially removed the entire upper door/roof section from the Escalade. I then cut the Silverado cab in the same manner, and just glued the severed upper door/cab portion from the Silverado onto the Escalade rockers and doghouse.The reason this second version isn't done is simply because I don't remember where I put the first Escalade donor kit, and I don't want to buy a second one just for its rear rockers and flares (I'm running the Escalade side cladding all the way to the bed).
Of course, you could save a bit of trouble by leaving the Escalade hood molded closed, and just making it a curbside, and slam it out on some huge wheels... which is probably what I should have done in the first place!