Glides

[spdracr39]

So I was reading another post and only saw one response to the question " Will plastic glides scratch/damage the hull? " I am considering this option and don't want to scar up a nice hull. We load and unload every weekend. I know it's the bottom and no one will see it but I am a little OCD about that kind of stuff. If I do add these to my existing carpeted bunks should I use the widest possible ( 5" ) or are the 3" going to suffice? My bunks are 2x6 and I have 2 10' and 2 6'. Should I try the slick em first ? Will it work the same way ?