frame swapping?

[msblackbetty79]

im hopefully going to be gettin a 2wd blazer but im wondering how are is it to swap to a 4wd rig? cause i love my 4wds.

the blazer is a 75 2wd.

I have a 79 4x4 truck frame 1/2 ton.

my question is could i chop the front half of that truck frame off and weld it onto the blazer frame? are they the "same frames" as in size and thickness? i understand the truck frame will be longer than the blazer but ill only need the front clip of the 4wd frame.

but.. how realistic is this idea?