This is not a popular boat here so that is why you have not received a response yet.
A quick google search turned up several posts on i-boats about repairs and remodels of the Spectrum 1700.
I am pretty competent in my "renovation" skills.
I would start with removing the top aluminum strip
by whatever means necessary to get it done.
on the side windows. Pull the glass out, there are
probably screws in the bottom channel that holds it down.
If you are not going to sell the windows or reuse them,
there is no reason to be gentle in this job.
just get started on it - figure it out as you go.
If you get the side windows removed - then comes the tuff part.
engineering brackets that will safely hold the windshield in the
new verticle position as you will loose the side brackets.
put a lot of thought into ------- either keeping the windshield or tossing it all together.
.