Are you standin' yet?
Artwork: My Daughter
you're carrying the chest, it's on your person, so yes it "projects" with you -- just as your items you're carrying and the clothes you are wearing do
- My thoughts
So ya think you can cast the spell from that projected spot AND throw the chest from there? Eh, who cares - it set's the target space regardless... either way it is an awesome move which won the game...
UPDATE: Ok, just realized a reason it would not work (and an example of how confusing Wiz-War can be). So the Heave-ho card is a mundane action - which according to the latest FAQ says is NOT a spell and is therefore "played" not "cast". The Astral Projection spell says "cast 1 target spell as though you were in that square.", so technically the Astral Projection/Heave-ho combo is NOT permitted.
Does this also meant that since they are not spells the transformations limited to counterspells can use them along with items? That would make sense... but difficult to remember and explain to new players.