It's a minor syntax issue, instead of using a comma you should use an ampersand (&), eg:
Code:
If Instr(FineArr(I), Get) Then Tmp2 = FineArr(I) & "SB =" & SBValue
(it is possible to use + but that causes problems in some circumstances)

You also don't need to use a temporary string, you can assign directly back to the same array element:
Code:
If Instr(FineArr(I), Get) Then FineArr(I) = FineArr(I) & "SB =" & SBValue