The only time I've used thermal paste was when I had to change the fan on our computer's CPU heatsink.
From what I remember the CPU has a flat area that the heatsink is clamped against. I put the thermal paste in between the two flat areas where it was before. Didn't need much but it was an expensive tiny wee syringe that I got from local computer shop.
No idea what the inside of light looks like but it should be fairly obvious where it goes.
Is the guy from Glasgow big_f_d_d? If so I found him on eBay when I was looking for these lights. He's selling Magicshine lights virtually the same as the lights the guy in my earlier link. £80 is more than the £67 that the mtbbatteries guy is selling them for. A lot more than the £30 odd that you can get them for from the Far East on eBay. Think I'll take the chance that the cheaper ones are just the same as the UK sellers much more expensive ones.
big_f_d_d's website http://www.torchythebatteryboy.com/p/magicshine.html
is quite good where he tests the lights and batteries. His tests of the Magicshine lights don't fill me with confidence as to the reliability of the Magicshine lights, chargers, and build.
Looks like if I don't get a reply soon from mtbbatteries I'll be buying from the Far East.
I did think about this light though,
http://www.ebay.co.uk/itm/250906539591? ... 1423.l2649
Again way cheaper than UK sellers who probably source their stock from same manufacturer.