Unfortunately have some loose skin I didn’t use to have but still have 5lbs to go and I guess that is what happens when you overbulk after 40
You have to weigh in within 26 hrs, so don't do anything crazy with fluids or salt, etc.
The open hvys might be a less tough open div at the Lt hvys...could be more tough or the same???
You won't know until you get there.
FYI, your abs look pretty hard and and most masters have a little loose skin.
You don't have that problem, so relax.
Now, just do more posing and RELAX. Good luck, you'll do fine.