Matt, I got Samson also when he was 6 and he had never been crated. His foster mom introduced him to it and I continued using a crate for a long time, due to separation anxiety...I found for Samson, putting a few treats in there helped, and using treats to get him in. Fill a kong for him and give him that also, keeps them busy for awhile

....Samson does not like the crate, I'll be honest, so he never got the concept of it being a retreat...Now Angel is incredibly good about being crated.. I stick her bear in there and just give her a bit of a nudge and she goes in, Very little fussing...And definitely, if they start to fuss, ignore it....That just feeds into their getting attention...
Good luck and keep us posted.....