Atwood Water Heater Tank Replacement Rings

[Jsterner]

I repaired the aluminum tank on my water heater and am ready to reinstall but would like to know if anyone has any tips on installing the metal rings.

[wasatchmtnatvr]

use an automobile exhaust pipe cut about 6 inches long that barely fitts over the alunimun flue tubes. Put a block of metal or 2x4 over it and hit it with a hammer to drive on rings.