I used the generic truck bed light strips sold on Amazon (link below) which required some trimming and resoldering for the center piece, along with a new switch from OTRATTW. The bottoms of the Utilitrack rails are a great place to stick the light strips, smooth for adhesion and are far enough out to light the bed well.

https://www.amazon.com/dp/B083S7FFMD/ref=cm_sw_r_cp_apa_i_Jr4EFbEVEQEZ9