Be careful with adding that weight(rim and tire plus mount) to your rear ladder. They are usually not strong enough to hold that weight. The bouncing up and down on the road places a lot of stress and weight on the ladder. The screws will pull out and your tire may be rolling down the highway behind you. You might consider a hitch tire mount that goes directly into your rear trailer hitch. It is much stronger. They can be found at most r v supply stores(Camping World, ETrailer.com, Amazon...).
Paul
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