No. The key words are "past the models last Wound" (pg. 13, pg. 15).
If a Model has 2 Wounds and has a Con of 6 and you roll a 6 to Wound, with a +2 Bonus (making the roll

you simply cause a wound, the extra points past the Con don't do anything.
If you do the same thing on a 2 Wound Model with 1 Wound left, or a 1 Wound Model then you are taking away their
last Wound and you modify the roll on the Injury table by the points you beat the last Wound by.