Noticed this post while checking out forums . PGUM tower does not control airspace around Guam. The radar station is actually up near Anderson Airforce Base (PGUA). Oakland controlls area encomp[Mod - Happy Thoughts]ing area north of equatorand includes Area from Palau to Majuro, Kosrai, Phonepi, Yap, Chuuk, Wake , Midway, Northern Marianas and Guam and any other out lying islands in Micronesia. Keep in mind that VATPAC only has the Nauru FIR and the southern chain of the Marshalls in the Nadi FIR (specifically Tarawa) in its airspace. The majority of Micronesia falls under Oakland Oceanic airspace and on VATSIM, they are all volunteer controllers from many different VATSIM divisions (not just VATUSA). As to opening a tower in Guam when you become an S1, I'm not certain who's division airspace you would fall under as the volunteers in Oakland Oceanic are all FSS positions (read that as Oceanic controllers) and I don't recall ever seeing PGUM_TWR online. Perhaps Norman or Mark can clarify this.
Well Enjoy your time in VATPAC and look for me online somewhere in the pacific