it's a 1uf 630v cap
check here for more on reading caps:
http://www.wescomponents.com/capacitor/
105k meaning 10 with a multiplier of 100,000 with the k representing 10%+- tolerances.
the first two digits times the third (5 representing the number of zero's; hence 100,000.
Edit - From what i have seen this is typically a 684k cap (68 times 10,000 = .68uf.) On the layout Stephen has a .62uf cap. Perhaps he just uses what he can get his hands on?
Edit 2 - After more research I have found that the higher that value on the cap the fatter the tone ofthe TMB channel. On the mods list Stephen says that if you want to try for a fatter sound you can try a 2.2uf in there.