Rears look to be the ones that go with the rear end.

Did a quick Google search on the numbers you posted and didn't find anything. Maybe you or someone else who has more time can dig deeper and find something. Otherwise, talk to Ralph at ECI, I've found him helpfull before. You might start by saying you think what you have came from his company and you're just trying to verify. If it makes sense to him he'll tell you, otherwise he might be able to give you a lead to finding the info.