Funny question, 170lb speaker and foam base, how to remove?.

Whenever I unpacked speakers from their original boxes if there was no instructions I would unpack them in a high ceiling room. By placing the boxed speaker upside down and undoing the flaps on the bottom and removing foam. The speaker is now standing upside down with it’s feet or platform in the air. Then with the flaps folded back on the box and help from friends carefully lower the speaker to it’s side and move it close to where it will be and place it right side up with the feet carefully on the floor. Now all you have to do is undo the flaps on the top and take out foam. Lastly lift the box up and off the speaker. For very tall speakers, you must have ceiling room to do this, otherwise do as jackd mentioned with the speaker on it’s side. It is always good to get those carpeted furniture rollers as Jacd  mentioned, because they really help a lot with placement and movement.

And they shouldn't destroy any of the packing in the process.

When I unboxed my T Refs (140 pounds), I laid them on their side over a padded bench in the living room and removed the foam from the base. Easy peasy. 

I'd get a bunch of couch cushions and lay the speakers down on them.  Then slide the speaker out onto a blanket or tip the box back up with the speaker still inside and then slide the box off the top.  I'm guessing you should have put the box sideways and taken the foam base off before standing them up.