On a Replicator 2 I've been using 4 shells and 50% fill to make sure they are almost solid so strong...Use Raft to make sure they stay well stuck to the build plate as they are quite small.
Get some regular picture hooks and high strength (to be safe but depending on the weight of the object being hung) double-sided foam mounting tape. Most hardware stores have this.
I recommend a quick wipe of alcohol to clean the flat (mounting) surface of the block before sticking the tape on. This is just to make sure the mounting tape adheres well to the block. The side you need to stick the tape to is flat and does not have an arrow on it. The arrow w side slips onto the picture hook and the arrow indicates "up".
Close the picture hook angle down a bit so the blocks will still readily slide on/off. By doing this you minimise the width once mounted on the wall but also need to ensure easy removal as all blocks will need to slide off simultaneously once stuck to the back of the wall mounted item.
Work out the required positing of the picture hooks and install them on the wall. Make sure you take time and care doing this as you are effectively going to tick your object to these points when you install it the first time.
Place a block over each hook with the backing tape removed from the foam mounting tape.
Now the fun part... carefully (noting any reference points you may have made) push the item to be wall mounted against the blocks (which have been pre-hung on the hooks). Push the item being mounted firmly to ensure a strong bond with the mounting tape.
I suggest removing the item from the wall to ensure the blocks are well stuck to it. Done correctly, lifting the mounted item straight up will lift it, blocks and all, off the picture hooks.
Once removed press the blocks firmly against the item you have been mounting to the wall. Once satisfied the blocks are well stuck mount it back onto the picture hooks... job done.
This is a simple process. It may sound long and difficult but really no harder than mounting a picture the usual way. However, I have explained the points in detail as you are effectively fixing the item being mounted to some fixed points. Taking care is important to ensure it works well.
Our Boomerang looks great on the wall.... you could even mount your favourite 3D prints the same way if you like the idea of 3D art on display!