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Obviously removing the old glue residue then a light sand and clean with some acetone like glueing a tub?
Sounds about right. My favourite clean-up solvent is isopropanol rather than acetone, just because it's safer (for your stuff; health and safety hazards are about the same) and does the job in most cases, but if you already have acetone at hand and know how to use it safely then go ahead.
I've bonded a seat post head onto the tube with Araldite, too early to say whether it was a success as it has only been on my MTB for a little over a decade. As with any glue job, preparation is 90% of the task. My go-to general purpose 2-part epoxy adhesive is this