The frame does not look to be original, and even if it is, someone has welded a bunch of metal to it, so any collector value that it may have had is only in the box, and that would need to be really clean.
I say play with it, paint it light blue and have fun.
I purchased a M416 that is spotless a few years back to use as a Mexican blue print for making a little red wagon to drag behind my junk…just have not had the time to start fabricating the trailer yet…