combining two grow tents into one

My basement is only 6' tall in some areas so the biggest tent I could find to fit is a 40" x 40" x 72".
That's not big enough for me so I was thinking of getting two and putting them side by side, adding zippers (or cutting) to open the sides and the hard part try and tape the two side openings together to make one sealed tent 40" x 80" x 72". Allowing me to run one exhaust system, one controller, and one co2 system, instead of two. This should work right? I did think about building my own, but it seems to be cheaper to buy premade tents and wrapping a 4x8x6 PVC frame in poly sounds like a pain in the ass

No input or other ideas?
Does anyone make custom size tents.

No custom tents to be found, mabye I should start a business making them. So since no one objects ill go with combining 2 tents. I knew it was a great idea.

go to ebay and search grow tent, some allthe way up to 10' X10' X 72"
most of the peeps on there also have their own sites if you would rather not order from ebay.

also search hydro sites. http://www.growsmarthydroponics.com/Indoor-Greenhouses_c_116.html

at those sizes it would be much cheaper to build your own.