B4 you do it, WAIT. Stands for "What Am I Teaching." Really. I've seen people makes mods to boats right when they get them. My recommendation is to wait a while. Perhaps actually take the wheel off when you're in port to open up the cockpit. You might also want to consider a smaller diameter wheel. Give it some time.
Then, if you're still convinced you NEED or want to do it, go ahead.
In most boats with wheels, there is a backup tiller location that connects to the rudder post and/or quadrant. Find yours and figure out how to do it.
There may also be an Islander 28 Association website or Yahoo or Google group. Have you tried a Google search on Islander 28?
Very, very nice boats.
Good luck.