Sell as is, there are so many parts in that thing and once you start pulling it apart you open a can of corroded worms! Unless you really know what you're doing then best to leave it to someone who does know and has the knowledge and required skills. Sometimes it works out well to mildly clean up pieces like this first to show the good points, but that also can bite you in the arse when things like the plating that is there flakes off and ends up looking worse! Also sucks when you find major flaws you didn't know where there to begin with, because if you're honest then that will have to be pointed out to the buyer. Replating is the killer these days. I pretty much just stay away from buying anything that needs much plating and stick to pieces with a good aged patina that I think look way better anyway.