Universal QA is 44 inches. So if the QA plate for the KL451 in 44 inches and the Skidsteer attachment is the standard 44 inches, you should be good.
I didn't want to throw out a general yes, because I remember reading somewhere, I think it was IT, saying that his factory QA was a little short. Also, I think Bobcat's older QA setup was propiratory.