I have NEVER even attempted using any filler of any kind.
im in the process of smoothing up my firewall a bit and need some help on where to start.

Just need a few low spots and dimples filled.
What’s the best route/products to use?

Later I’ll be tackling the body, same materials?

 

If all you're doing is filling a firewall, you could probably go to Walmart or somewhere and just buy a can of "Bondo". If you are going to use on the body in a visible area get some high quality stuff at a auto paint supplier, etc. It's really quite easy, just that after you mix it use immediately. If it starts to roll up and harden on you as you are trying to spread it- Stop! Don't try to apply it if getting hard. Just throw it away and mix a new batch and continue. As anything else, you'll figure it out. That's a good place to start and learn.

 

Apply to bare metal not over paint, don't forget to get sand paper.
Steve

 

Actually, modern epoxy fillers are designed to be applied over epoxy primer with no issues.

 

Any brands or product names to research or stay away from?
I'm completely new to this.
Thanks!

 

Be sure and mix thoroughly whichever product you buy. The chemicals will separate while sitting on the shelf at the store. If you don't mix them well before addition of catalyst, it will harden/cure with mixed consistency after the catalyst has been added and mixed in This situation will cause you to start over with a new batch. Not a huge deal, just wasted time and product, as you can't work the material if it is not cured properly.