The dee-dee stops are made on the assembly station. It's one page after the water tank (which has a blank page next to it, the page after that is the dee-dee stops)
The material you'll need:
- 5x Hardwood plank
- 4x Bronze pipe
- 6x Bronze plate
- 10x Fiber cloth
Never seen Presley levitate, but how do you mean higgins is cheating? Do you mean with sparring, trying to get a commission, or trying to beat his workshop with commission points?
And yes, Antione is probably gay, if you chat with him he'll talk about how he likes the male doctor. Higgins is rude, django is eccentric, oaks digs through trash, and there are kids skipping around. It's character personality and development, better than all of them acting the same to the point you can't tell them apart, no?
As far as having trouble reading the book while Antione is near it, it helps if you go behind the desk sometimes. I do agree that it'd be nicer if it was placed further away.
As far as I can tell, completing the dee-dee stops will not allow you back into that Amber Island cave. It closes after you finish that quest. If you want to farm it, you'd be better off restarting the game and avoiding finishing the quest so you can keep returning.
Hope that helps