I will be mounting my 2-port fuel pump on the firewall in the engine bay. I am not worried about vapor lock as many others have mounted theirs back there without issue.

Question is that I need to pick up some drills bits for drilling a couple holes for the mount bracket. I've only got a simple black and decker cordless drill. Am I going to need something a bit more powerful? Or do I need to somehow start the holes (tap?) before drilling them? New process to this weekend mechanic.

Just drill it, but do it right !

That's what I'm worried about....the doing it right part. Last thing i need is a swiss cheese firewall.

The lower fire wall is two panels spaced apart. You are going to need to use self tapping sheet metal screws. Drill a hole no larger than the shank diameter if the screw. Drill one hole and install the screw. Mark the other hole and drill it. A cordless drill will work.

How much space is in between the 2 layers of sheetmetal on the lower part of the firewall where I will be installing? Do I want to be drilling all the way through both layers? Or just one and find a short enough (and stout enough) sheet metal screw that only goes through one layer and still does the job? :-)

I removed my back pad and drilled through both layers and used long bolts with fender washers. I double nutted the bolts. Maybe overkill but it has held up for 20 years.

Or...... you could use self drilling/self taping screws and eliminate the drill bits.

Here is a picture of a cut out firewall looks to be about 1-1/2 " between the panels.

I was super cheap and borrowed this from my friend.

http://www.harborfreight.com/45-piece-thre...r-kit-1210.html

I plan to buy one though when its on sale.

Then I bought some 2 rubber isolaters with studs on both ends and threaded it in and then put the the pump on top of it, just imagine like the original layout of the FI pump.

No need to remove the back pad, just stop the drill after you made it through the first wall.

What I've done is bugle the hole with progressively larger punches, so you have plenty of metal and then tap it M6