2008 Ramlin trailer bunks

[CincinnatiCC]

Hoping someone else has run Into this issue. I have a 2008 206 and trailer. Bunk carpet has worn over the years, so replaced it two years ago. Now the bunks seem to be sliding off of the metal frame of the trailer. The trailer frame is a closed channel, so it seems like the only option is to screw down through the wood bunks into the metal trailer frame. Is that right? And assuming that is the case, are you using stainless or some other heavy screws to get them to last?
Thanks

[peteb]

When I replaced the bunk carpet on my 2000 Ramlin trailer last year, several of the self tapping screws were loose when I tried to re-tighten them all. Since the odds are the frame was just rusted and there was no steel for the fastener to grab when tightened, I just moved them to a new location. I used a wood paddle bit to get the recess and then simply re-used the old self tapping fastener. I cant remember if the self tapping screw was stainless.