I don´t like your method, br. raycopper. I usually test the swingarm play by holding a finger in the gap between frame and swing arm, near the bushing. With the other hand i wiggle the rear wheel or the swing arm directly. If you feel more than 1 mm play consider the bushes to be replaced. Hitchcock´s, btw, supplies bronze bushes instead of the stock plastic ones. I think this could be a hint for it´s susceptibility for wear.
I doubt, though, that the bushes have passed away. My bike shows not the slightest play at. 9500km. But using a steam blaster too close is a commomn reason for the early death of frame bushes, as well as making many wet miles.
Maybe it´s the wheel bearing. If you have the wheel out you can test is best, and you could grease the brake cam too