[support] Premium Content Search Question

[Fred Jones]

I am building a site with premium content, meaning only paid members can 
  read content in our archive. Anonymous users can search the full 
database, to determine if the information they want is there. For the 
search results, the boss wants to show:

The first 150 words of the relevant paragraph, like Google Scholar works.

I am uncertain how to achieve this. Seems like modifying function 
search_excerpt in search.module might do this, but I'm not sure if this 
is the correct approach.

Can anyone shed any light on this?

Thanks.