You can add a button (but you'll have trouble getting it next to the other locator buttons, without some serious hacking around).
But once you have the button this will hide the locator:
p_web.Script('document.getElementById("locatorclassid").style.display = "none";')
This will display the locator:
p_web.Script('document.getElementById("locatorclassid").style.display = "block";')
locatorclassid looks like this (but you can confirm by inspecting the elements on your page and finding the div that wraps the locator and its buttons:
if you place your browsers in memory forms
swap the _b_ for _a_ to swap between the before and after locators.
You'll need to add a button (somewhere, i'd put it in a memoryform that is a parent of the browse, but its not going to be next to the other buttons). Plus you'd need to match Bruce's logic when he hides and shows the locator.
Bruce also has his own code that hides and shows locators:
Which you could also use.
So in short, its possible, but probably not worth the effort and could be very hacky. Better to ask Bruce for a feature request.