There was a discussion about a military coup on arrse a while back, it was decided that unserviceabilities/overstretch mean that the RAF would have to use the BBMF, the RN would have to make use of HMS Belfast and the Army would have to stop off at the National Army Museum on the way to Westminster.
As long as it got rid of the current bunch of self-serving gits (all parties, not just Labour) I'd be happy laying siege to Downing St with a pick axe handle.