Neither manual explains CRT removal and replacement.
The best that can be found is an exploded view, attached below.
@Saul: The set screws located in the front panel controls are likely to be 1/16 inch (0.062 inch) hex. Some may be 5/64 inch (0.0781 inch) hex and possibly 0.050 inch hex. These set screws can be surprisingly tight. Attempting to use metric hex keys that do not fit tightly can result in damage to the set screw. Once a set screw is damaged it usually requires drilling. Drilling is difficult because the metal is hardened. This is one job where there can be no substitute for the correct tools. In the US we refer to these as "hex keys" and "allen wrenches." Hopefully these can be found in Brazil.
RF+ Tech