After reading a simple guide by 1200xl over on the RCM forum, I decided to give this retrobrighting thing a go.
Retrobrighting is a process of removing the yellowing that tends to occur on old plastics. I’ll not go into the science behind it cause i don’t really know it.
As a test subject I used the casing of one of my Fluke 9010a pods.

I ordered some peroxide online and this Saturday was the ideal day to try as to make this work, sunlight is required.
Apply a nice thick coating of the peroxide to the washed down plastic and wrap it in clingfilm, then place it in the sun for a few hours turning it every so often to get all sides.
Probably should mention that rubber gloves are a must for this job as the peroxide doesn’t feel good on bare skin!
After its been roasted, remove the clingfilm and wash off the peroxide and let the plastic dry.

Pleased with the results for a first attempt and have since don’t the body of the Fluke with better results.
I was advised to apply a UV treatment after this as the yellowing will return but at this point I haven’t got any. I’ll get some ordered though.
Will no doubt have more stuff to do in the future.