Hitachi 55EX9K Red Problem

[Anomonis]

Hello, we have one of these old (1994) rear projection hitachi models and the red is becoming distorted. The colour leans to the centre of the screen horizontally. I cannot correct the error with the convergence settings.

I am wondering if this service mode I have heard about may be able to help?
Does anyone have an idea of how I can find out how to access service mode with this TV?

Alternatively, we may need a new Red CRT i think. Does that seem reasonable? Also is it possible for someone to replace a CRT by themselves without the aid of a technician?

Thanks in advance.