I know this is very late for this question but I had this same situation. As others have said - I create two inventory items. One is "discount" of -$1.00 and and the other is an "additional" of $1.00. Then I manually do the math and add the it to the bundle. If the difference is 13.46 less then I just do 13.46 of the "discount" bundle. Since I have it set as a negative it works as a discount.
Total pain when the prices change as I have to manually re-work everything. Would be so much better to be able to set a bundle price.
