Concur, time for the tlc you are planning, definitely need to arrest the cancer or there wont be much to salvage. Have to commend you on your undertaking, while most of the underside is actually pretty darn nice off those few problematic areas will be nice to know are not getting worse.

I thought the ground effects just slide off the clips, could be wrong, but thats what I remembered. Remove end screws and then slide it forward. Been a minute. a few years, but that is the best I remember.

 

I got the ground effects off and posted pictures in my other post, fixing up my 03 monte. most of the rocker looks good except the front, the front looks extremely bad and will need new steel welded in. Looks like i'll be learning another skill. Or i could have my uncle weld in a piece, hes a welder for a living. but I would have to source the steel and get it shaped, and i have no idea where to do that,