Install electrtic fuel pump

I am going to install a Holley "Red" pump in my '72. I have a "Relay" kit and I plan to remove the mechanical pump and use the electric full time. I want to connect the "trigger" wire to ignition so that it all starts up when I turn the key but don't know which connection would be the best. Any and all suggestions welcome!

I also want to include a safety shut off and would appreciate any input on whether an "inertia switch" is better than an "oil pressure" switch.

Thanks in advance for any and all input on this "fun, easy DIY upgrade"! 

Kinda surprised no one has replied to your questions yet.  If you have an owners manual I would suggest looking in it for a list of fuses, and perhaps there would be a diagram of the fuse block.  When I put a TBEFI system on "BLKBRRD" I needed a "key hot" connection and the owners manual had the info I needed to find one.  An Assembly Instruction Manual for your year should also have that info in it.  If you don't have one of those I would highly recommend getting one.

Sorry I won't be able to provide any input on a safety switch, never ventured into that arena.  Hope someone else can jump in and offer up some info.

When I replaced the carb on my '75 with a Sniper EFI, I used the wire that used to go to the electric choke for the power.  You could also probable tap into the wire that goes to the distributor.

There should also be a spot on the fuse panel that is hot both while cranking as well as key on.

Either way I'd use these taps to activate a relay that gets power directly from the battery.  A fuel pump can draw quite a bit of power.

Not sure about using an oil pressure switch for a safety switch for the fuel pump -- it would not be active until the car was cranked long enough to produce oil pressure.  Depending on the car it could be almost instantly or a few seconds of cranking.

Actually, on my '72, the wire that goes to the idle stop solenoid is hot when you turn the ignition to ACC and I think it stays hot during start.  I use it for my electric choke.  The radio is on the same fuse.