I've already purchased the materials for this. Just waiting for a day thats not in the 30's to try it 
Wow, do you know where I can find the materials for this in Australia? No one around here will sell me the peroxide so I've never been able to make any RetroBright to lighten up my yellowed 1200s and 500s. I have washed them though, and they come up very nice if you use some Gumption.