My suggestion is to consider taking the opportunity to upgrade to tankless system. I suggest the Furrion Tankless Water Heater, # FR68SR as this would be close in dimensions to what you have including door size, which is 18"x18". This is designed to replace 4 - 6 gallon water heaters and has a wall mounted controller. The tankless design has a heating capacity of 2.4 gallons per minute with a vortex system that mixes hot and cold water to eliminate fluctuations and reduce the risk of hot... view full answer...
We do have something for you. I was able to locate the owners manual for your 2000 Coachman Catalina 5th wheel, which told me that Lippert is the partner they use for their landing gear. Unfortunately they do not tell you what system exactly is used or measurements, this is not uncommon as they do not always use the same system for everything. It often comes down to availability.
Landing gear jacks are often interchangeable with each other so you would need to look at the bracket stop... view full answer...
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