Thanks guys for the input!
The ramp was for a family member who has passed away, but the remaining adults are are of those years where such a ramp may prove helpful before too long. So I want to help them preserve the ramp. My sense is that exterior carpet is tacked/stapled down, and so I am hoping popping it off can be done fairly easy without critical damage to the carpet. If it can, then I definitely want to lift it and get the wood protected (carpet extends to about 4 inches from edge of sheeting). If not, that's an added cost for the homeowner for which I want to be sure he is prepared. I do want to be sure to preserve the traction of the ramp as mentioned.
Need to figure out what this looks like in labor... Thanks!