1) remove all plumbing fittings to new comode. If never been removed in a while, be careful, you could bust the pipes. I would at this time install the flex line anyway. Its a good investment.
2) Drain all the water from the tank and bowl. I use a sponge.
3) Seperate the tank from the bowl. This reduction in weight makes it easier to take to the alley or wherever.
4) Remove the two bolts on the bowl flange holding it to the floor. You may have to hax saw these bolts off, the urine and stuff pretty well corodes the stuff frozen shut. Do not worry about damaging any thing in this process as it will go to the dump.
5) Now the real messy part. Stuff a rag into the sewer hole. This keeps the gasses out of the room and make sure that you remove this rag befor you put on the new bowl.
6) Get a putty scraper and remove all the old wax and stuff. Remove the old colar and bolts. Throw this stuff away and you should have a new wax ring and bolts handy. This comes in a package. Be careful, you can buy the ring separetly or in a set.
7) Install the new water line and use teflon tape at all fittings.
8) Set the colar on the floor pipe and set the wax ring on the colar. The bolts will be setting straight up, but it better if you attach a straw to each bolt. this will give you a better guide when you try to line up the bowl on the bolts.
9) Install the bowl and now attach the tank. Now go ahead and attach the water line to the tank, use teflon tape again. Attach all the innerds to the tank. This is all done with out applying weight to the bowl.
10) Now this is the touchy part. Here we are tightening the bolts on the bowl flange to the floor. If you tighten them too much, you could break the flange. If you do not tighten them enough the thing will settle and it will be wobbly.
I usually get a deep socket and run the nut down on the flange hand tighten on each side. Then alternatively take a turn on the right and the left side. Tighten down evenly. periodically sit on the bowl and waller around alittle to compress the wax ring more. Tighten up the nuts again in the same manner. Again, sit on the bowl and waller around again. Now tighten up the bolts again. Do this procedure until you cannot tighten them up any more. Remember, easy as it goes. When the bowl is easly and securely fastened, your weight on the bowl will not cause the bowl to shift one way or another. I always check the nuts again after a couple of days use. you will find that they are alittle loose again.
*** This is very easy, its messy, smelly, and heavy.
remember, teflon on joints, tighten the bolts very easy and do not ratchett down on the socket set. These are not lug nuts.
Now you can sit on the throne and do your business and be proud. No butts about it, you did the job.