I doubt this will have an effect on case temperatures, but try it. Also, make sure to post your results. The fans are there for a reason and if you were drawing tons of power or had no case ventilation it would be a problem, but you should be fine. I posted here and a few other forums about modding the Truepower. At a different forum (can't remember which) I was told to just remove the bottom fan permanatly. There was even a user that claimed to run his Truepower 430 (with a small system of course) with a single Panaflo L1A controlled by the Truepower. I am going to mod mine with a 92mm Panaflo L1A and 80mm L1A or H1A. I will try to see which works best. Anyway, you should be fine.
Brian