Finally got the frozen nut off the bolt yesterday. Didn't have to
use the hacksaw.

Apparently enough 0f the liquid wrench stuff had soaked in, and when I
tried it
Friday morning with the wrench / vise grips and screwdriver I was able
to get
the nut off and the tank dismounted.

Got the bowl out easily, and started pulling the old sheet vinyl and
thats all
coming along well.

Still thinking about the tank bolts though.

Nowadays, almost all toilet seat attachment hardware is the nylon bolt type.

Why not nylon bolts / nuts for the tank / bowl attachent?

When I was at Ace Thursday afternoon picking up a new wax ring for bowl
re installation, I looked for nylon tank attachment hardware figuring
that
I'd have to replace the nut / bolt I thought I was going to have to saw
through.
No such animal. Only brass tank attachment stuff. I didn't think to
ask the
guy at Ace, who is usually pretty knowledgable. I picked up a set of
brass hardware,
which I will eventually have to return.

Anybody know why apparently no nylon tank bolt attachment hardware?

Second issue: I'm cleaning up the bolt threads in a wire wheel in the
drill press. All nice and clean now. Really interesting aglommeration
of green, blue,
white and all shades in between of corrosion and crud now gone. It was
concentrated
where the nut was on the bolt, and below the nut.

Any thoughts on a lube or thread proctectant for the
bolt threads before reassembling things so I don't run into this issue
again?

(Yeah, I know, if its another 37 years on this specific toilet, it will
be someone elses problem, not mine.)

But is there a reason not to use a simple lube like white lithium grease
or even
vaseline on the brass threads on the bolt and inside the nut?

Thanks.