I'm in the same boat as you. There is another thread about brake controllers, I'll see if I can find the link, where another member explains what the part numbers mean.

Long story short, I just ordered the second one. Made sure you get the CB and not CA, or BA or AA for the newest version. Basically the "higher" the last 2 letters are, the newer the version of the part.

Edit: here's the link https://www.f150forum.com/f118/trail...345407/index4/

 

Thanks

 

Jl3Z19H332AA is the newest, both are the same

 

That link also describes that the 19h332 comes with the relay and fuse, so if you already have a tow package you won't need that.