I'd say put the Colossus somewhere behind the Sathanas. The only problem I found with this, with logic, is that another Sathanas could jump in behind the Colossus. That's instant death--a Colossus trapped between two Sathanas. They'd be fried by the frontal barrage if they stay and they'd collide with the forward Sathanas if they try to jump. Anyways--the GTVA would probably jump the Colossus in, in a situation where they want to destroy it, in the rear. The GTVA isn't a tactical genius, but they're still not stupid.
Anyways--bombers and a Colossus is definitely the best way to kill a Sathanas. You need bombers to be precise and the Colossus to start the hurtin'.