If you consider the differences between the Drake CST743S 1.6gpf and the CST743E 1.28gpf being the fill valves and flush valves, TSU24A & THU129W-A and TSU53A & THU252P-A respectfully, since both use the same bowl, CST743E, is it possible to convert the Drake II CST454CEFG to 1.6gpf in the same way?
Now, you may be asking, why would I want to do that? Because to get CEFIONTECT on the Drake I'd have to go with a 14+5/8" bowl (CST744SG) instead of the ADA 16+1/8" bowl and I really prefer the Drake & Drake II sleek bowl look to the Promenade's blocky front bowl (which makes me think of a 1930's toilet or hospital toilet.)
Now, you may be asking, why would I want to do that? Because to get CEFIONTECT on the Drake I'd have to go with a 14+5/8" bowl (CST744SG) instead of the ADA 16+1/8" bowl and I really prefer the Drake & Drake II sleek bowl look to the Promenade's blocky front bowl (which makes me think of a 1930's toilet or hospital toilet.)