Surface Rust Removal and sound deadening removal

I've decided to turn my 2012 Civic Si shell into my next chump car. It's got a lot of surface rust on some pieces from being out in the elements for about a year. Just wondering what people use to get rid of surface rust.

Also the floor board has a lot of sound deadening that's a huge pain to remove. Any tips on how to get this tar like material to come out easy? I've tried an air chisel on the 94 accord but Honda makes their floor boards paper thin and that air chisel went right through the floor pan.

Block of dry ice and set it on top of the sound deadening material

Sine_Qua_Non wrote: Block of dry ice and set it on top of the sound deadening material

and an oscillating scraper.

You could always try "rust converter" on the surface rust. I think it's Phosphoric acid' which converts the Iron Oxide to Iron Phosphate, which you can put paint on.

I think I remember hearing that ATF does interesting stuff to rust, too.