From left to right: 300x Maroon with red cap - £19 from ebay looks horrible but its complete and came with good Bialaddin glass, vapouriser is good (tested on another lamp). Full restoration is planned for this one to original painted finish. Despite it's outwards appearance it only needs a reproduction cap, new air screws, mantle, seal kit, paint and a few hours of tlc to make it look like new. 300x Brass with black cap - this was once a maroon lamp (paint still present on tank bottom), an early example with pressure indicating pip. Found on a car boot sale and paid £20 for it, glass was cracked but I had a good spare in stock, lamp so far fettled to good working condition. I don't like the polished brass look so plan to repaint this lamp and restore it to as built condition. 300x Green with green enamelled hood - bought as part of a job lot (£25 for 3 lamps). Lamp fettled to good working condition and unless I can find a good replacement hood (or find somewhere to re-enamel hoods) I will be leaving this lamp in its current condition.
All good as far as I can see - your fettling plans are just what I would do with those three. I think the pressure tit made a brief re-appearance from 1947-48ish. Your electrical installation is very neat - I just wish mine was as tidy!
Found a leak on the tank of the left hand lamp, where the control valve screws in, tell tale pizz poor solder around the joint, all sorted out properly now, added approx 45 mins to the restoration. Re wired the garage last year, don't like seeing twin and earth pinned to walls and only costs a few pounds more to hide the wires in plastic conduit.
I also have a couple in my restoration queue (but have a load of Scout Group Tilleys to service first). I think they are great lamps but its a pity they are let down by the poor quality/manufacturing of their hoods. I have quite a few in the scrap box where the hood itself is unfortunately past caring...
Yes, I think it's generally accepted that the standard of British vitreous enamelling is not up to the standard of the US equivalent i.e. 'porcelain'. However, I think it's worth bearing in mind that these lanterns weren't designed to have an extended life (maybe 10-15 years maximum, at a guess) so the fact that they're still with us after 5-6 decades is reasonable testament to their original quality of manufacture. Everything wears out at some point and needs to be replaced...