What's your handicap? Most toilets are setback 12
inches from the wall but they're are toilets setback
at 14 inches...And they're are handicap toilets taller
than the regular toilets... And toilets with different
sized traps and surface water measurements, so you do
need to take a few things into consideration...
Once the toilet has been removed, just take a
measurement from the back wall to the center of the
toilet flange/drain pipe...Are you replacing an older
model that uses 6, 7, or 8 gallons per flush or are
you replacing a newer one...
A lot of people are dissatified with the newer toilets
because sometimes you have to reflush to get all the
waste out of the bowl and into the sewer line...
On the box the toilet comes-in you'll see a
measurement for the amount of water surface, left
remaining in the bowl after a complete flush...
You really want a toilet with a larger water surface
measurement... What this does is; it allows the toilet
to hold more water, so it floats more waste and helps
to complete a flush with just one flush
everytime...And trap size is important and glazing of
the trap is also important...Bet you didn't know so
mush crap about crap before...
With some luck,you'll pick-out a brand and model that
will work just fine, but we answer posts like this
several times a yr...
If you had a 14 inch setback and installed a 12
setback model, you could attach a length of 2x4 behind
the tank and low enough to be out of eye sight and the
tank will rest on the 2x4 or I believe I've seen
offset flanges but those can create additional
problems for you...Good luck...E.T.