I'm a day away from putting together some CUTE little Minion cakes - they are essentially:

2 6in cakes, stacked on top of each other with a 1/2 ball pan can as the topper.  

My plan was to use my trusty SPS system but I just realized (doh!) that when I've done a barrel in the past, my SPS plate in the middle of the cake is an inch smaller that the actual cake so that it doesn't stick out and cut into the fondant.  Crap-o-la.  Any suggestions?

I would prefer NOT to use bubble straws as it is set to be 108*F tomorrow and this is for a pool party and I would like this cake to have all support I can give it.  (It wont be in that heat the whole time but I do have a 45 minute drive to get it there - even with the a/c on full blast, my car is far from cold)

Actually, I solved my own problem.  Dremel to the rescue!! I now have lovely 5in SPS plates! :)

Two 6" cakes for a total of 4 vertical inches?  Plus the half ball?  Honestly, you can do that without internal support.  (Don't flame me.  I've done it)  

No flaming! :)

No...two full 6in cakes (each being 4in high each) plus a 1/2 ball - so a total of about 10-12 inches.  I ended up dremeling the SPS plate (they have nifty little  "nubs" on the under side that I used as a guide) to make it smaller in diameter.  I wish they would make a 4in plate.  I use it simply because I am guaranteed that as long as I drive like my grandma, my cakes will arrive in tip top shape.