Nice. There aren't a lot of round pattern 205s around.
Assuming the one with the black bellhousing is the black one, GM didn't paint bellhousings other than overspray and not black. That suggests a PO painted the TC.
How's that for sketchy pseudo logic with no facts. LoL
My guess is that the (GM destined) TCs were painted in some years with red primer that in some cases lasted and in others didn't. The color/paint may have been different in earlier and later years.
The Sub I parted to get the 205 from was a 3/4 ton w/ a semifloating 14 bolt.