I had the same issue. I ended up getting longer bolts. Driver's side, you can't permanently install the longer bolt as it bottoms out on the body, but I used it to cinch one strap down, then used the longer bolt on the other side to get it all the way down. I then replaced the bottomed-out longer bolt with the original .
The original bolts are M10 x 1.5 x 35mm long. 35MM is max for the driver's side (maybe 40mm) but you can get a longer bolt for the pass side