i drilled the holes for my retainers and used bolts to hold them in since the holes were all the way through. the top retainer isnt what im worried about now though its the bottom one. its at an odd angle so when i drilled the holes there was only maybe an 8th of an inch of plastic on the edge of the retainer left. does that make sense? not the way it is but my wording.
it seems the plastic is sturdy so i think it will be fine. only thing left to do is paint the bolts black since it was either sliver or im going to say brass. and i used black posterboard to stop light from bleeding around the marquee. yey me.