You could make a macro!

Steps:

1. Use a find string with wildcards for the variables (if the variable is a cell reference as in your example 'H157' all you need is a single asterisk '*' in place AND you need to ensure that you are searching the values NOT formulas)
2. Click 'Find Next'
3. If you need the variable i.e. 'H157', and it is at the end of the existing string, use [End > Shift+Left Arrow > Copy], if not modify as needed.
4. End Button, to get to the end of the current reference string
5. Type in the new addendum reference
6. Paste your variable from step 3

If you then add a loop to the macro, it'll automate the process for you.

If you create the macro and paste the working code here, I'll help with the loop if you want.