I am having a problem changing the seat on a Kohler ONe-Piece that must be over 10 years old .... This may sound very confusing to you ...

The oldseat was loose and when I pulled up on the hinge area, the seat just came straight out ... there were no screw nuts or anything (why it was loose, I guess!)

What is more strange is that there is no access from under neath the toilet bowl as in other models, so i cannot understand how to replace the seat and what typoe of seat to buy.

In the top of the bowl there are two holes (1/4 inch) ... but when i look down ... nothing ... inserting a thin screwdriver ... it just goes straight in ...

Inside the tank the flush mechanism seems to screw into a separation in the tank wall and i can see that water goes through there to flush ... this inaccessible area is where the two seem to go down into ...

If anyone recognizes this model, please let me know ...
Thanks
Antony