Your bimini tubes should separate in the middle. You should then, be able to cut them down to fit between your tower uprights. Then, you would need to take the fabric to someone to have it cut down as well.
I don't know of anyone who has actually done this, but it should work.
If one day you're asked:
" How did you spend your time here on Earth?"
Will you say:
"I kept a crabgrass free lawn"
It's time to SKI.