mixer taps impossible?

i have to change the mixer tapes on a bath! unfortunatley they are in such a position that i cant get any standard tool including the swivel basin spanner, around it, i just dont have the space to get to the back one, due to the wall and the position of the sink pedistool. any pro got any good ideas on how to tackle this one as i am only a ameture as you can guess,cheers
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