Nice upgrade!
You can send your room requests in through DSS (you otherwise can’t actually contact the GF directly, any # that says it’s GF will go to a call center).
When you book a CL room, you may or may not hear from DSS. Sometimes they call, sometimes they send a post card, sometimes they do both, sometimes you hear nothing!

But regardless, you can reach out to them at any time:
Disney Signature Services
(407) 939-7777
disney.signature.services@disneyworld.com
So Main Building Standard CL rooms.....most are on the third and fourth floors with maybe a couple on five. The pic below is the fourth floor, which is the same floor as the lounge. The third floor is roughly the same and is where the CM desks are located.
There are two “banks” of standard rooms - a cluster that faces the Courtyard Pool and another cluster across the atrium that faces the Villas/Beach Pool/Poly.
My room was the red dot below. LOVED this room, convenient to the lounge, convenient to the “secret elevator” that goes down close to Gaspy’s.
Pics below that may be helpful.
FWIW, my only room requests were “fourth floor, close to the lounge.”
Others will likely have additional advice/perspective as well.
Have fun!