'71 800 Getting better!

[MikeIIDC@domain.elided]

Well, the 800 that I asked about the exhaust for last week got a little
work today.  Actually, it was only as a result of my shifting lever
going out in my '64 T'all that I got to working on it.  I have four IH's
sitting in the driveway, only one of which is officially a non-runner,
and yet, none of them were working well enough for me to take it out to
the auto parts store!
So anyway, it was the one that was backfiring so terribly that I was
afraid of blowing out the exhaust in the one mile I drove it home.
Well, I took the coil off of my wrecked '68 T'all w/345, put it on the
304 in the '71 Scout, and the backfire is gone.  It still does not sound
GREAT by any means, but I think a little timing work and it will be much
better.  I definitely did blow out one of the new mufflers, though.
Anyway, question #1:  The '71 had a small condensor mounted on the coil,
the '68 didn't.  I switched the coils and left it without the condensor
for the moment, and it was running pretty good.  I just want to make
sure I'm not going to fry anything while I'm fine tuning the
thing/possibly driving it a little.
Question #2:  The thing does have a "knock" of sorts-can't exactly
locate it-seems to be on the passenger side of the engine, down low, but
of course, that is a very subjective analysis.  So what all is going to
cause a knock?  I know it is a bad sign, but am curious, as there are
always those people that claim to have had a knock for years.  The
dipstick that is in it is not stock, and is VERY homemade.  I don't know
how accurate it is, and doubt it is very accurate at all.  If there is
too little oil in there, can this cause a knock?  I ask because when I
had some engine trouble with my '68 T'all, and it was idling VERY
roughly at one point, I got a big knock-diagnosed by me (I know, doesn't
carry water, but there was a real good old-fashioned mechanic that I
trust right there, and he said-"That's a serious knock!  Main bearing or
_____" Can't remember what other bearing he said).  Once I had ironed
things out, and had RPMs back up, there has been no knock since.  So if
oil is low or oil pump is going bad, can this cause a knock?  Or should
it only cause some lifter noise?
Well, that should do for now.  Any advice is greatly appreciated!

Thanks!

Michael