You won't regret it...
I use a FiTech system, the Go EFI 4 – 600 HP System, I didn't use and don't recommend the Command Center, 90% of complaints about this system are directly related to it.... I use a Tanks Inc tank, pump & fuel level sender... I used assorted fittings & a fuel filter in the rear of the car...
Completely agree here; I just installed a Fitech Go EFI 400 system on my 52 Dodge pickup which has a 56 Desoto 330 Hemi in it. I too used a Tanks Inc. tanks and fuel pump. One key point here is that you need to match the fuel pump to the EFI system requirements, if you don't you will likely have issues. Not hard to do, just read what the EFI system requires for inlet fuel pressure and find a pump that matches it (Tanks Inc has whatever you want). I also used a Tanks Inc tank and pump in my 70 Challenger with a EFI 6 pack system. Good products overall and fit well. Some things to consider;
1. Which EFI system to use - there are many on the market all offering all manner of attributes. The core of this is how much control you want over the system. there are a variety of "self learning" systems out there to include Fitech, FAST and the new Holley Sniper system (essentially the same thing as the Fitech but allows you to use the Holley V4 software to manipulate it if you want). Then there are the more versatile systems such as the Holley HP system (there are numerous others) that require you to use a laptop to input a tune and then refine the tune to meet your needs. I have a Holley HP system, a Fitech (self learn) system and a FAST self learn system. I haven't gotten the car with the FAST system up and running yet so I cannot comment on that, but between the other two, the Fitech was WAY easier; essentially bolt on and go. \
2. Fuel system design - this is a place that many don't fully embrace and are surprised once they get into it. On the one hand, you can use a stock tank which you will probably have to modify in order to accept a return line, then use an external pump and filters to deliver the fuel to the EFI system (Throttle body or fuel rails). Or you can use a new "EFI ready" tank with an internal pump, or you can use something like the Fitech command center (basically a canister that takes fuel from your stock system and then turns it into a high pressure system your EFI system requires). Out all all of these, I believe it is pretty universally agreed that the EFI tank and internal pump is the best. Visit some of the EFI manufacturers and do some research. Just understand that there is no "free lunch" and while it may seem cheaper/easier to just use an external pump and existing tank/lines, you may be disappointed in flow/performance as well as shorter pump life and pump noise. 2 more things; you HAVE to use filters (the type and quantity depend on your fuel system design) and you HAVE to use a return line to somewhere (either the tank or to the command system) despite what some manufacturers advertise. I helped with a MSD Atomic system that advertised "no return line needed" only to see on the first page of the instructions "return line highly recommended"; we ended up installing a return line to get it to work right.
3. O2 sensor - you will have to install an O2 sensor into your exhaust system. There are a number of ways to do this ranging from clamp on systems to weld in systems. Fitech comes with a plate that allows you to do either.
4. Wiring - The wiring will depend on what system you select. The Fitech and the Holley sniper system require about 4 wires to be hooked up whereas the Holley HP system (or any direct port injection system) requires the installation of a complete harness (not hard but much more designing and installing).
5. Electrical requirements - Every EFI system demands clean power to operate correctly; this means being wired directly to the battery and having access to "switched" and "cranking" power. This has caused a lot of confusion and problems but isn't that difficult.
In short; installing an EFI system does require a bit of work, however as stated you will not regret it (assuming you install the right system correctly). You car will start, idle and run FAR better than it ever has. It will be more drivable and more importantly more fun to drive. I grew up on carbs like many here, I was tuning 6 pack systems when I was 18 and rebuilding Holleys and Thermoquads frequently. I have now replaced every carb I have with an EFI system; this includes 6 6 pack systems and 1 brand new Holley 600. I will never buy another carb if I can help it. EFI can be a little daunting especially if you go to a tunable system, however it isn't magic or impossible. Kids are doing this daily on imports without even thinking about it.
Hope this helps