The first expression deletes any group of spaces that are at least 25 spaces long that are preceded by a |. It also continues deleting anything until it reaches the next |. After the first expression you are left with 

'|       FIRST LAST NAME|       ADDRESS 1                             
+                                Interest Rate                        
+     5.450000|       CITY                         STATE ZIPCODE|     
+                           Total Payment Amount                      
+$886.00|';

[download]

The next expression will remove any set of 25 or 27 or more spaces that are not immediately preceded by a |. It will continue deleting spaces and anything else until it reaches another |. It will delete the spaces after ADDRESS 1, since there are more than 25 of them and keep deleting up to and including 5.450000. Then it will look for another match (/g). There are 25 spaces between CITY and STATE. Those spaces are not immediately preceded by a |. So it will delete those spaces and keep deleting STATE and ZIPCODE until it finds another |. By increasing the 25 to 27, you keep it from matching in this case.

In reply to Re: Negative Lookbehind question by ExReg
in thread Negative Lookbehind question by crusty_collins

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