I'd pressurize the tank like they do to diagnose leaks in modern evap systems.  I am not sure how much pressure to use but I am sure you could google it.

What about the filler hose.clamps?

Never heard of sealer on O-ring connections. What did you use?

To pressurize the tank, take a bicycle innertube and cut it and clamp one loose end to the filler neck tube.  Clamp oter end shut. Use schrader valve to place NO MORE THAN 5 PSI inthe tank.
Spray CRUEX on all fittings. The leak will show up in the cruex powder.

MS wrote:

What about the filler hose.clamps?

Never heard of sealer on O-ring connections. What did you use?

To pressurize the tank, take a bicycle innertube and cut it and clamp one loose end to the filler neck tube.  Clamp oter end shut. Use schrader valve to place NO MORE THAN 5 PSI inthe tank.
Spray CRUEX on all fittings. The leak will show up in the cruex powder.

 
The orings are under the screws on top of the mounting flange. Kinda poor way to seal through holes into the tank. I used Permatex Ultra Black RTV.

Maybe I could spray the Cruex on the fittings and drive it around to see if anything shows up.

It smells more near the pump and sender openings.

I laid a towel over the top of the fuel tank and took a 30 minute drive. I removed the towel and you could smell fuel on the bottom of the towel. But I could not detect the exact spot of the vapor leak on the tank. Just somewhere on the sender or pump.

Yep, you need PTFE (teflon) hoses. My stainless steel braided rubber hoses decomposed in 2 years

What are you using for your vent hose? I have the same tank and the top mount has two fuel line ports and one vent port. Where is that routed to and what materials are you using?

Ditch the RTV whether Ultra or not.  It is no good with gasoline.  Usually those screws going into the tank have a nylon washer under the head so they can seal.  I had used one of those expensive Phantom Aeromotive pumps on a 70 tank.  Even with the nylon washers, their special seal and Teflon ID hoses, there was still some seepage around the gasket.

This is a dangerous situation as gasoline fumes are explosive.  Much worse than a liquid gasoline leak.

One more reason I went back to trusty carbs.

Well, you guys were right the vapor smell is coming from the braided fuel line.
I wrapped a shop towel around the pump side fuel line in the trunk, wrapped tin foil around the towel and wrappd tape around that. Ran the electric fuel pump for several minutes and let sit over night. This morning I unwrapped everything and the shop towel smelled like raw fuel. I Iooked back at my Summit Racing receipts and saw that I bought Summit brand braided hose as well as Russell braided hose. I am not able to tell from the outside braid which brand I used for that length of hose. Looking at the left over pieces, the inside rubber hose is constructed differently between the two. Will have to remove hose end to see what brand it is. 
But, how can Russell and/or Summit sell fuel line hose that weeps fuel vapor after use? I am totally baffled.

I don't think any of that hose is rated for fuel injections higher pressures.
I'm with Kelly, any oil, fuel, or hydraulic hoses I make now are PTFE based.

I installed a Tanks Inc tank w/ Russel lines I purchased through them and have a few smell as well.  Haven't figured out where mine is coming from yet, nor had I figured out how to find it.
Will have to check my lines to see if they are ptfe or not.
 

My last fix for the fuel odor was to go to the PTFE lined hose. I ended up with a Fragola brand from summit, and it has worked well. I used the Fragola hose ends as well so it was all one brand. I chased my problem all over the back of the car, but my fuel smell was in the passenger compartment. Ended up being the hose from the hard line to the engine. That little bit of hose caused all that smell without any visible problem. My fuel pump is in the back along with a filter and regulator, so there are lots of connections back there so I thought that had to be where the problem was. But no, that 10 inch piece under the hood. The hoses in the back were already teflon.