I thought you read this post within this thread https://www.turbodieselregister.com...2387626&highlight=intake+ductwork#post2387626 (since you did reply in it) but maybe you forgot or overlooked it.
The air filter housing cover does not have to be removed, but it's a great time to inspect the air filter also.
You mistake me for someone who has a memory, sorry.
You have the older style frame.....completely different from the OP's. The oil filter can no longer be accessed from the bottom of a 2013 & up RAM 3500 or a 2014 & up RAM 2500.I get mine from down under. Two 12 inch 3/8 extensions and a cap style wrench. Break it loose
and reach up and change it out. Of course long arms help.