Great, thank you for the information and links. I was confused because I wanted to try the Fusion type. Now it makes sense, no standard in the fusion line. Thanks again.
If you really, REALLY wanted to try the 510 Mega Fusions in your standard tank, you
could but about 10mm of the cartomizer would stick out of the top endcap like a very long drip tip. Purely an aesthetic issue, not one of functionality.
I know people who do this intentionally, including my ECF buddy Zapped. He uses Smoktek 45mm length cartos in his Phiniac standard length tank.

I believe his reasoning is because he fills his cartotanks (wrong

) by removing the top end cap off of the tube but not all the way off of the carto. He then adds e-liquid between the top cap and the tank tube.
Not a method that I personally recommend, because replacing the top cap via this refill technique could result in flooding the carto from the sudden increase of pressure inside the tank. But Zapped somehow gets away with it and has had success using that method. It keeps him off the smokes, so who am I to argue?
Besides, the endcaps of IBTanked are so tight on the pyrex tube that the above fill technique would be difficult to do on a regular basis.