I bent my subframe over the winter and ordered one from a salvage yard that was in great shape. However, when I received it, I noticed the part number stamped on it had a different last letter than the one I have listed in my parts manual. The manual had a part number of 4A0399313L and the one I received is part number 4A0399313B. When I search for 4A0399313B on the ECS Tuning web site it tells me this part is not available and that it was superceded with 4A0399313L. So, is there any reason I should think that these part numbers are interchangable? Anyone know what revisions were made to it?