Statement of purpose imposes word limit, but I already have a significantly longer version. Can I submit it as it is?
I would think that two and a half times the maximum would be a bit extreme and leave people less than pleased.
A few extra words wouldn't hurt most likely, but what you suggest seems unreasonable.
Factor out the most important ideas and express them concisely. Consider it a test that you don't want to fail.

A note on the SoP. Don't use it to reprise what is in the CV or other materials. Don't use it to explain past problems/issues. Make it entirely forward looking. What do you expect to accomplish in doctoral study and thereafter. You are wasting words if you try to use it for other things.