Hi, I recently acquired my first ever Optimus lantern, a 350. Reading around on here I think it dates to the 1970's? It looks very similar to a Petromax HK500 without the pressure gauge so I was wondering when I come to light it do I light it as I would with a tilley/vapalux or like a Petromax and build up the pressure first? Also, will a petromax mantle fit although I realise the HK500 mantle is 500cp, not 350. The lantern needs a good clean but I was wondering how best to approach this. Normally I use autosol and a cloth but this crud seems to be fairly well ingrained on the base so can I use fine wire wool and autosol or would that damage it?