mark
+1y
welcome to the forums
SE-5 and LE-5 are just trims of the truck, like Ford XLT, XL, FX4, etc. etc.
6lug chevy wheels will fit, but you have to get the center hole bored out to the size of the mazda stock wheel bore size, they will fit without modifications to the suspension but that also depends what size tires you get, so just by getting a bigger wheel doesn't mean you're going to sit up higher, you'll have to get bigger tires as well
you can try moving the stereo head unit to that spot under the vents, you'd have to take that dash bezel off and do some cutting, its been done before
goodluck with everything, if u have any other questions, ppl here should be able to help