Trying to replace a toilet. I bought the new Champion by American
Standard, we had 2 at the last house. When trying to mount it the left
bolt through the flange was at an angle, it's back a little too far.
No I can't adjust it, that's as far as it will slide due to the way
the flange was installed.

So, I put the old toilet seat back on. Seemed Ok, no leaks, until you
use another drain in the house, then sewer gas comes up.

Also, the left side of the flange is cracked where the bolt goes
through.

So, I want to replace the flange, but I can't. I did this on my last
house that was a crawl space, but can't figure out how to do this one
because of 2 things.

1. Concrete slab. Not sure how to get to it, where to cut off the old
section, etc.

2. This is the BIG problem, the current flange is Round of course on
the Outside where the bolts go, however the Inside Hole is Oblong. The
actual drain hole is in the front, Not in the center of the flange.

I believe #2 is why the sewer gas problem. I used a standard wax ring,
when I removed the toilet again tonight, I saw the front of the toilet
the wax ring still looked like new. So, hopefully just a Jumbo would
fix that part of the problem.

Any ideas how to replace the flange or how to get a bolt to line up
with the current on on the left side?

I took pictures if anyone wants to see exactly what I am talking
about. I did stop by Lowe's on the way home tonigh and bought 4
different flanges, none of them will fit.

Thanks in advance!
Sam