Hello all,
My hoses had dried up, they were cracked and if I touched them they would fall apart in my hands. I replaced them with 1 1/2 ich flexible sump pump hose and connected them to the heater box with 1 1/2 inch ABS fittings. Perfect fit and the hoses are flexible enough to go around the different components under the dash. As for the oblong ports on the heater box, I used 2 1/2 inch to 1 1/2 inch reducer ABS fittings. I put them in a vise and slowly heated, the 2 1/2 inch end of course, with a propane torch while tightening the vise. I put a 1 1/2 inch ABS pipe in the fitting to prevent it from deforming. They took an oblong shape and fit perfectly on the ports.