Relentless skid plate vibration SOS

Excuse me if I'm posting this in the wrong area, still a newb and getting used to the forums but I'm in need of a little advice/ help.

First off I only have a basic understanding of mechanic work so if anything I say or a part I name sounds wonky I apologize, anyway!
I installed a full set of skids (IFS/mid/tcase) from relentless fabrication last week and am now getting a vibration (it doesn't sound horrible but it's annoying as all hell to say the least) from what sounds/ feels like the front of the truck. I've triple checked the install & referenced the installation guide, and am sure I've done everything correctly.

My mechanic and I installed an adjustable bilstein 3" lift kit with 5100 shocks about 6 months ago which included half inch diff drop spacers? Or spacers for the oem skids, both, anyway relentless informed me the spacers wouldn't be needed so in installing the new skids we omitted them,

So long story short after crawling under the truck with a flash light it looks as if my front diff? If that's what it is, is indeed resting on the ifs skid. I'm thinking maybe putting a round of washers in between the ifs and the truck to give the diff a nice millimeter of room might help but, I thought I'd throw a line out to see what you guys think, or if anyone has experienced the same problem.

Pic included was the best I could take for reference

Thanks ahead of time and sorry for the ranty &probably not needed first few paragraphs of info!

 

Remove the diff drop

 

^ correct. Remove diff drop, and if needed space down the skid with plastic spacers if needed.

 

Thank you both for the info and answering my probably stupid question

 

No worries. Welcome to the forum.