I would say your best bet for up front is to get the Kick Pods/panels from Crutchfield for your truck... the are already formed to location and have room for the 5.25 compnent system. you will just have to mount the tweeter up on the dsah or on your door somewhere.
but like he said PITA running wiring through the rubber channel.
6.5" fit in our doors with no sheetmetal modification. you can make some plates out of 1/4" MDF or plywood to fit over the oval factory hole or get some adapter plates which are made by Metra and Scosche for 10-15 depending on waht your local audio shops like to charge
I used 1/8" aluminum, I know I have the luxury of having it. But I did the same, just cut out somewhat larger than the oval and cut out 5.25" hole in the center. Then I just used self tappers to secure the plate. I put eDead on the back to prevent rattles also.
i put some 6.5 comp's in my 01 mazda 626. i used 2 pices of 1/4 hardbord and cut one to opening of the orignal speaker size, and another ring for the aftermarket speaker. i used some gorilla glue to stick it together.