Unless you buy a shop manual, you're not going to find a Haynes or Chiltons repair manual for just one year or one specific GM car. Haynes and Chiltons are going to cover a set of years of a certain model of cars and they will mention the year to year differences as they apply.
As far as that goes, you're not going to find a shop manual for just the Bonneville, it'* going to cover all C/H platform cars, because under the skin, they are the same car. The Bonne, the LeSabre, the 88'*, 98'*, and Park Aves are all built on the same assembly line by the same overpaid union workers.
The differences, as they say, are only skin deep.
1996 Olds LS, 198,900 miles: RIP...