Need Advice on Paint Prep/Sanding

so for all of you painters out there, i need some advice. i am trying to paint the ram air covers on my f4i. they are made out of that plastic that is textured, like bumper plastic. i have been sanding it for a while with different grit sand papers, but i cant seem to really get the texture to go away. should i get out the electric sander?

any tips would be appreciated. what grit should i start with, and what should i end with?

No!!!
 
Don't touch it with sanders!  If you really need to sand it then get a sanding sponge.  They're real cheap at Walmart or anywhere and will work for what you need.
 
Are you just getting it scuffed for painting or are you trying to sand scratches out of it?  If so, how deep?

Didn't catch that last part...
 
As for grit, it really depends on what you're doing.

220 or 320 should work fine, 150 if its really messed up. My F4's wasnt all that textured, but I covered mine in CF vinyl.

im trying to get it so its super smooth, like a regular fairing. i want to paint them so that they are gloss black. i will work it with some sanding sponges like you said. luckily i have one that i can test with and not really care about it.

Wet sand it with some 400 gritt sandpaper. Should work perfectly. Put time in it too.......and use your hands to see. If it doesn't feel perfect, it's not going to look perfect.

sand it with what the other guys said and the paint coats will get it super smooth. whatever texture is left after sanding, the paint will take care of it.

Personally I would not sand it...you can buy a special plastic primer that is meant for textured surfaces...the primer is real thick and will lay flat...I had mine professionally done and he said not to sand them...the primer and flex agent should fill in all the texture. IMO, sanding is a waste of time on the bare plastic