I'm having more trouble with this then I did with beating a Brutal opponent. Any tips?

A common answer here would be: Play as russian, against a team of 3 Gileses. Swarm the first with flak troopers, while building air defences and Kirovs. Then Swarm the second with the Kirovs. Replace those that get destroyed and swarm the last Giles.

So in other words exacly like this video:

Coi Cki, is it me or does your post seem familiar , I'd personally prefer the death aquatic map and build a crusher crane then relocate to the middle part of the map while building your base up where your crusher crane is, then do exactly what Coi Cki says