Greg E.,
Harris Hill has a parking area for trailers and tow vehicles as illustrated in the below picture. Spectator Parking and Paddock Areas are also highlighted.
For securement of truck bed and open trailer contents, there are two options...
1) Find a friend with an enclosed trailer to stow your items (I can recommend a whole list of folks.)
2) H2R has an office within the clubhouse, that will have constant supervision.
