Take pride in flying that thing till it disintegrates. They are made to fly, not be um.....'purdy'. I have some darn nice engines hidden away by cheap fiberglass cowls. Your plane should be well maintained, but a well-used engine will not look new for very long.

Fly it and keep it running well, but don't worry about the anodized color. There is nothing you can do to keep it looking new.... aside from keeping it...um...new, (i.e. not flying).

Welcome to the DARK SIDE.....mwahahahah...and to the end of 'Free-Time' and 'Disposable-Income' as you know them.