"Cheap tech" to keep the mud out of the frame :)

[TNT]

Keep the water, mud and salt out of the holes in the frame that allow access to the upper control arm bolts.

 

Use the crankshaft access plug from a late '80s to '90s Mopar cars and mini van splash shields on most vehicles they built.

 

They fit directly in the hole on a XJ. A MJ has a extra steel tab that needs to be trimmed slightly.

 

It may be stupid simple tech, but it works great to keep water, salt and mud from getting into the frame.