Right so its in!
Had to remove the tube guard and then the amp section to get at the speaker, after that its 4 10 sized nuts which are a bit of a pain to loosen. Once out new one slides in no problem and tighten up. I did however not look at what colour the positive wire was.. but the first post in this thread has a pic and it seems like yellow is it.. (anyone with a C30 confirm that?)
How does it sound? Well obviously it has to break in but from the get go.. ??? What an improvement! Breaks up early, its more tonally in the range Im looking for. I found the Blue Marvel to be too toppy in some cases, especially with a strat it can be like glass, the Greenback is warm and punchy and makes you want to play harder. The biggest suprise is how different my fuzz pedal suddenly sounds.. with the Blue Marvel it was a bit sharp and harsh but with the Greenback the mid hump it seems to have puts it right in the right place. Crunchbox sounds raunchier! TS9 with a bit of dirt is my favourite still.
Will leave an mp3 player on it for a while and see if it loosens up.