Hi,
if you opt for the ski-pass-through option, then depending on your golf bag, you might be able to slide it through the pass-through hole into the trunk when the top is down.
the trunk space, even with top up is not gonna hold your golf bag, at least couldn't hold mine...
and i dont have pass-through, so i just leave my backseat down and wrap 2 beach towels at each end of the bag so it doesnt scratch leathers on both side.
you can fit 2 golf bags using my method, and just secure them with seat belt, works great when i take my dad golfing
cheers
Michael