Buffer between corner guards & 2" receiver on rear crossmember
So I'm in the process of bolting corner guards onto my rear crossmember, as well as reinstalling my SG 2" receiver (also bolted to rear crossmember).
I currently have no rust on my crossmember, but I know that things like to "rust" (or more accurately rot) when you bolt things to the rear cross. I've seen it with NAS bumpers and such over the years when you press two pieces of metal together (I'm assuming it just traps moisture/etc in there).
I've painted/sealed the parts that will be bolted on with Eastwood rust encapsulator & top coated with chassis black to help separate the metals, and seal them prior to installation.
So my question is should I add in some sort of a "buffer" between the two metals where they bolt on? I have some heavy duty EPDM rubber that I was thinking of using...but wasn't sure if this would help avoid rust by putting a layer between the metals, or if the same thing would/could happen and it would still encourage rust by trapping moisture.
Any input is welcomed.