Yeah, putting a cover on the 5.0TA would not be fun. It's not especially fun on the 21 and I'd hate to be up even higher.
We use two ladders and stand on either side of the trailer. We pull it up from the front, although I like the idea someone showed on putting it in the middle first. Might have to try that next year.
Anyway, we also use these 2 poles (Access 70950 EZ Retriever II) that I keep in the back of the truck for pulling/pushing stuff around in the bed. They're strong enough to support the weight of the cover and are easy (for us) to grip.