" How much slack is there on the top
fittings when pivoting the tank down? Will it drop enough to get to the
front top of the tank?"

Jerry,

Barely... mine's a diesel, so may be different, but there's a vent line
that runs across the top of the tank between the drivers and passengers
side and runs over stuff that doesn't move (see Bentley's to see if
gassers are the same), so you have to disconnect it before the tank will
drop down.  That's not too difficult, but putting it back in was a pain.
Required a skinny arm to reach in through the drivers side wheel well
after placing the vent line in on the passenger side.  Maybe there's an
easier way, but it took me a good while to get that cross vent line in
place.

While tank is out, you can inspect the top for rust - that's where mine
rusted out from crap/moisture sitting up there.  If it's good, clean it
good and cover with auto undercoating spray to protect it another 20
yrs.

Think about replacing fuel lines and vent lines as well as fuel tank
grommets while you've got it apart unless its been done in the last 15
years.

You can also grease the shift rod bushing above the tank that never get
grease - you'll like shifting for a while after that:}

Maybe others will have more suggestions for prev. maint. while tank is
out?

Have fun,

Chris