Anyone using these with the OEM drop in bed liner? If so, did you have to modify anything to get them to work?

 

The Builtright Bedside Rack system will most likely not work with a drop-in bed liner. You would probably have to do some cutting of the liner and it may end up looking kind of jenky. I just removed my drop-in liner on my 2018 last week and will be installing two Builtright racks this weekend. Ditch the drop-in and get yourself a good rubber bed mat.

From the BR website:Ford F-150 & Raptor (2015-2020)

* Fitment Note: At this time, we cannot confirm fitment compatibility with all drop-in bedliner systems, as the various manufacturers take different approaches that are difficult to account for. The same applies to some hard cover tonneau covers with clamps that can't be repositioned. Some customization may be required in those cases.