Basically the same you describe.
We sell and service them in the shop where I work and you're correct they are difficult to work on. They are too heavy for a stand so I use a plastic milk crate when necessary and generally have to sit or ??? on the ground to work on them.
They are a pain but for those that need them and want to ride they are wonderful so worth the aggravation.
We also use a ratchet strap hanging from the stand. It also works but can be a pain to balance the trike. But it does work...kinda sorta...