Yes you can use the method suggested above and if you are trying to preserve the board finish use a new scraper and be careful of sand which will scratch the board. I use Shellite or White Spirit(Hydrocarbon so use a vapour mask and well ventilated in the shade - not windy)
If you have an old sheet lay this over the deck pad area and trim to the outline with sharp shears. Cut a piece of builders plastic eg GRUNT from bunnings about 50mm bigger than the outline.
Decant the solvent into a smaller container so you can control quantity - I find the **johnsons & johnsons baby powder dispensers handy for even distribution(squeeze very gently) - and soak the sheet and eva foam pad underneath - start in the middle and work to the edges and careful not to overflow.
You will have to work quickly as it evaporates fast - cover with plastic and tape the plastic onto the board as best you can and press out any voids.
Leave this for 15-20min and if you have sealed it all up properly your grip and glue should all but slide of and using a bag of clean soft rags use more of the same solvent for cleanup wiping in a circular motion.
To safely take care of the rags you should drop them immediately into a bucket of water, rinse out and then dry out in the shade in single thickness - not screwed up. If you leave them in a heap the combinations of chemical compounds could self combust
Always use eye protection
Always use reparatory protection
Always use chemical resistant gloves and protective attire.
ALWAYS DISPOSE OF SOLVENTS AND SOLVENT SOAKED MATERIALS WITH EXTREME CARE
**do not use with acetone or thinners EVER - the bottle will melt. These solvents will eat your paint too
Go with piece