I know you need an Up Grade and a Dubious Disc for the Porygon Evolutions. So, I have a Dubious Disc, but how do I get an Up Grade?
Gold Silver Crystal -Kanto: Silph Co
FireRed LeafGreen -Rocket Warehouse, Trainer Tower (Defeat Single Mode)
Diamond/Pearl -Eterna City (From Professor Oak)
Platinum -Route 224, Eterna Galactic Building
HeartGold SoulSilver -Kanto: Silph Co
Get it from professor oak, trade porygon with upgrade for porygon2, thean with dubious disc for porygonZ