background...
our house is 2 years old thus all of the fixtures that came with said house are basically new.  Wifey decides that the perfectly good toilet is too low and she needs one a bit taller.  I agree cause I was at a loss as to what to get her for xmas and this seemed like an excellent white trash  ("My name is Earl") gift.  Last friday I purchase Bowl and tank cause I'm not sure about the interchangeability.  I tell her I'm gonna install it after work on tue.

Tue:
wife: can I help you?

me: sure can

wife: -dissappears-

I finish  installing the bowl and decide the tanks are all the same (both are 6 LPF and use the same flush mech) and I decide to save a few bucks and use the original tank.

wife: arn't you gonna use that new tank?

me: naw, their both the same I figure I'll take the new one back

wife:  (flushing the new comode) look here it dont look like its flushing all the way!

me:  its fine I checked it

wife:  no look again it won't flush the turds all the way out!

me: its  fine I compared it to the other ones

this went on for 30 minutes until I ended up screaming at her in front of her mother   Finallly  I decided I was basically screwed as there was no convincing her  otherwise  so I install the new tank

wife:  hmmmm, it works the same I guess you were right after all

me: didn't I tell  you, we've been through this same argument before concerning things mechanical

wife: well I just thought ...womens intuition and all

5 mins later  

wife: look its leaking

me: no its still filling

wife: no its not working right, the other one would fill-up a lot faster and the water would stop moving...see

me: there's nothing wrong

wife: arn't you gonna fix it?

me: didn't we just go through this exact same arguement?

I'm guessing he is tells us all about it because he hasn't gotten any pie since.