I finally got around to fixing that annoying rear seat back rattle. The PO had electrical tape wrapped around the seat "bolts" but it quickly wears off. I have heard of using vacuum hose as well but never got around to trying it. I ended up just swapping the latches all together. I noticed the latches on my '90 62 parts truck were slightly different than the ones on my 60. There are rubber pads that push the bolts against the latch arms and eliminate any movement. I pulled the old ones out, threw the new ones in and problem solved.
Sorry, if this has been covered before, just thought i'd share.
My originals ('86 60 series)
the 62 latches:
Sorry, if this has been covered before, just thought i'd share.
My originals ('86 60 series)
the 62 latches: