I bought all the stuff to test my heater core: heater hose, clamps, barb fitting adapters, 1/2” cap, and a gas pressure test gauge at Home Depot for about $34. Then while driving I saw an old time radiator repair shop and talked to the old timer ... lo and behold he fixed the leaks in the heater core for $45 well worth the money, now I’m returning the test stuff to Home Depot
