Another silly, non-technical question from a newbie.

I have new Westfalia decals to replace the old wearing ones on the pop-top. Been waiting for warmer weather to put them on. What is the best and safest way to remove the old ones. The new decal is one big decal. The old is the individual letters. 

I was originally recommended to use this attachment on my drill that is like a rubber eraser, but I had not been able to find this. 

What are your recommendations?  The fiberglass is dark grey, so I want to avoid discoloration. Thanks!!

Jeremy. '87 Vanagon

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