Question about firewall.
 

Today i pulled the dash out of my project. As you can see in the photo below, there are a few holes to fill. Would it better to fill the holes from the interior firewall or fill it from the engine side? Or is either side a viable option?

http://i438.photobucket.com/albums/q...psdrandmqh.jpg

Thanks

Re: Question about firewall.
 

The side that is the easiest to weld, grind and metal finish from.

Re: Question about firewall.
 

David…A method I have used for years to fill the holes in the firewall is with nails with a large diameter head (un-galvanized). Insert them in the hole from inside the car, standing in the engine bay hold them in place with Visegrips, then tack into place after preparing area around hole. Turn wire speed lower and continue to tack to fill hole using the nail as the filler, 9 times out of 10 the shank of the nail falls to the floor. You then dress it back with 50 Grit. An old body guy showed me that trick to fill moulding holes on a set of doors back in the oxy-acetylene days (40+ years ago). Good Luck…Maurice.

Re: Question about firewall.
 

David, It really depends on what kind of finish and look you are trying to achieve.
As Larry said, you'd probably want to fill and grind from the engine side.
For a quickie, you could make one patch panel that would cover the heater hole and surrounding small holes, all in one shot. Pop rivet it on from the front. A couple of 1/4 -20 bolts and flat washers for the remaining holes , a can of Krylon semi, and you could be done in an hour. All up to you.

Re: Question about firewall.
 

I maybe want to return my car back to stock one day and have basically same question, can I just pop rivet or bolt a piece of aluminum over the whole heater fan opening using existing holes?
I like the idea of using nails, I have other projects to use that idea on.
Just had to return, after thinking of the nails, just had to say that's one heck of an idea, my mind is racing now.

Re: Question about firewall.
 

I am lazy, so, I would use some body panel adhesive on a piece of metal and put it on the inside of the firewall. When it is cured you can finish the engine side smooth and paint. No warpage of the metal and no fires. If it hold quarter panels on cars it will hold those small pieces. In the old days I did it with bondo and they stayed. Mickey Mouse but it works :)