I would like to add Bourbon to my pecan pie...how much can I add to get the flavor and not over-liquefy the filling? Will I need to add cooki

In addition to filling or instead of adding to filling you might make the vodka pie crust and sub bourbon for the vodka...https://food52.com/recipes/24966-cook-s-illustrated-foolproof-pie-crust

I'd go with 2 Tablespoons (4 Tablespoons = 1/4 cup) but if you want a strong liquor flavor, you could go with 3 or 4 Tablespoons.

Not sure what the rest of your question was? "Will I need to add cooki...."

I believe 1/4 cup should do it.