Ganesh...Sounds like your asking the same questions I had concerning the area behind the dash. Once you remove all the gauges and everything else, just use a small wire wheel on a rotary tool or drill. The rust back there shouldn't be as bad as the outside of the dash. All ya have to do is remove the loose scaley rust and maybe paint. You don't have to get it down to bare metal. Make sure you have the proper goggles on because you'll be looking up most of the time. That's all I did. Then I brushed on some encapsulating paint to seal it up. That's it. Believe it or not, it'll look good and give you piece of mind knowing the rust back there has been taken care of.
