Purchased set of 10 X 2 1/2 brake kit based on an 87 Chrysler 5th Avenue. Application is for Mopar 8 3/4 with Moser axles 5 on 4 1/2 bolt pattern. What are my concerns in selecting a brake drum that will fit properly. The 5th Avenue is finned unit which I do not want so changed my vehicle selection which used non-finned drums. Rock Auto provided extensive application list for many of these non-finned drums. Is it safe to say these units will fit. The big question is axle flange to housing flange offset. How do I know it's correct? How do I select a drum that will fit properly? What do I look for when specifications are provided?