Repair TV w/ convergence problem
 

I've got a Rear Projection Samsung HCM4215W who's blue gun is severely
warped. See photographs he

http://www.hardwooddesigns.com/forsale/convergence.htm

I want to repair it (buying one is NOT an option). How can I determine
if the "blue" emmiter (gun) has failed or the circuitry behind it?
Under the TV's convergence setup, I can still make convergence
modifications to blue, which behave properly, but its basic warped shape
may not be modified. I found that samsung has a service manual for the
TV that costs $20, is this going to help me w/ both diagnosis and
repair? Armed with a soldering iron and multimeter, I await advice.
Thanks in advance!

Brian