1993 Chevy P30 fuel pump help

Here's my experience with the fuel pump in my Itasca '94 P30. The fuel pump went out 3 times in the past 3 years, mainly caused by ethanol corrosion to the sender unit connections, and possibly a rusty ground on top of the tank. The sender unit was finally replaced at the last failure, as the gas guage was also showing erroneous readings. Been running fine for over a year now, and I also use CRC fuel treatment (1 oz. per 5 gals.) with the ethanol gas. However, the new sending unit was only for a 60 gal. tank and I have a 78 gal. tank. Those sending units are hard to find. Just have to remember that my fuel guage is measuring only the top three fourths of the tank, and the bottom of the fuel pump is at a quarter tank. Will be searching for the full 78 gal. sender unit to get the fuel management back to normal, but will need to drop the tank again to replace the sender unit.