Hmm, You can't do what you want where you want it.

You can store "Hello Steve good ___ing"
and "morn" and "even"

Yuor routine then reads "HELLO STEVE GOOD" from code memory (MOVC commands), reach your "__character" then branch to the "morn" or "even" bits of string as needed. If you use a non-visible character like #0 for a string terminator, you can readily jump around your snippets of code and output data to the LCD.

Steve