Cat converter Heav duty vs. Light duty

1988 f250 extended cab 2 wd auto with a 351 v8 130k miles. Truck is classed as a heavy duty. What is the difference between the heavy duty cat for 600.00 or the light duty for 160.00? Truck is out of DEQ range that means no emissions testing. The truck is used for hauling a camper 3 times a year. Can I get away with the light duty catand not lose power? They are both a direct bolt on replacement.