replace selected text in ical summary

I’m new to applescript and would like help replaceing selected text in a ical event. I have a calendar “School”. There are a number of events with titles, summary?, such as “MC (SEB)”, “MC (JCD)”, “JCD (MC)” and so on. I would like to write a script that looks for all of the events in “School” and replaces each occurance of “MC” with “My Company”, keeping the rest of the string as is. The end result would be “My Company (SEB)”, “My Company (JCD)”, “JCD (My Compnay)”. Can anyone help with this?
Thanks,
Steve

Model: Mac G4
AppleScript: 1.1
Browser: Safari 412.2
Operating System: Mac OS X (10.4)

Try this:

tell application "iCal"
	activate
	set ASTID to AppleScript's text item delimiters
	
	get every event of calendar "School"
	repeat with thisEvent in result
		set newSummary to summary of thisEvent
		
		if newSummary starts with "MC " then
			set AppleScript's text item delimiters to "MC "
			set newSummary to every text item of newSummary
			
			set AppleScript's text item delimiters to "My Company "
			set newSummary to newSummary as text
		end if
		
		if newSummary ends with "(MC)" then
			set AppleScript's text item delimiters to "(MC)"
			set newSummary to every text item of newSummary
			
			set AppleScript's text item delimiters to "(My Company)"
			set newSummary to newSummary as text
		end if
		
		set summary of thisEvent to newSummary
	end repeat
	
	set AppleScript's text item delimiters to ASTID
	beep
end tell

Thank you, that did the trick. I was trying to do this using change, but I just couldn’t get it to work.
–Steve