Some other factors in Water heater replacement
Went through our water heater replacement about 6 months ago. Anode only material only about 1.5 inch long. No wire? Had it done and took about 45 minutes. Replaced a 6 gal with a 10 gal and now we do not run out of hot water during every shower. Same size fit in 2008 Sierra 345RET. Have a spare anode on hand for next year. Could have installed largest unit in same hole if it had been immediately available.
The 6 gal may have been an earlier replacement - found some on-site info that this started with an 8 gal. The key was that an $1120 job only went up to $1195 due to capacity increase. With little documentation from the factory or vendors it becomes pretty hard to figure some of this stuff out. Previous owners took pretty good care of the unit, but it is getting old. We just live in it at a fixed location in East Texas so it might be "stationary" on our land.