Is lowering a BMW 1100 GS Possible?

I am short :-\ (ok, VERY short - 1.58m or 5ft2) and would like to be able to ride my husband's 1100.  I don't come close to touching the ground, although the seat is in the lower position.  I have a 650 that has been lowered (seat, shocks and spring) and wondered how much one can do to the 1100?

I have ridden a factory lowered 1200 and it works for me, but the 1100 is not only an antique,  it is paid for!  Any advice on how or if I can make this work, please?
And idea of costs?