Thats exactly what I have to use, and a thin plastic or thin metal attachment will work but it all depends cause some plastic will melt, and some metal will get to hot leave melted edge which in the end more work for you to sand, your going to have to just test attachments on other plastic man, goodluck to ya post some pics if you end up doing it PM me if u have further question

I used my trusty Dremel yeterday to mod my xbox steering wheel (put in a metal bearing), also ive used it years back to do all sorts to my flat before i was married.
For a long lasting, top quality rotary tool, Dremel is the way to go!!

PS: My dremels cordless, so i had to charge it after a lot of use, but id reccomend it as theres no wire to hang over parts/get in the way etc. - Though the benefits of not charcging are obvious, so its up to you.
But take it from an old man, - Dremel is best!!