Have to say I personally lean towards not restoring but for my relics I simply add some pieces and then spray black with a metal preservative paint. Only for visual effect as this black does not look like the blueing effect. The paint can be removed, as can the other 'added' items to return the piece to ''as fond'' condition. I have played it safe on purpose. Vickers images to follow. In the pipeline I have 2 relic MG08s incoming, one on a sled and one with its trench mount and another MG08/15.
Mark