1955 glass fuel filter bowl

[55 ledsled]

Mine fills all the way up. I had a similar problem after putting in a seal kit on my gas tank. The engine would not stay running because it wasn't getting enough fuel leaving air in the glass bowl. So I figured it needed a pump so I purchased one...same issue. Then I realized that I may have plugged up the pickup tube with sealer when I blew into the fuel line, so I drilled out a hole just below the pickup tube on the tank, and was able to get a drill bit in it and cleaned out the tube. But once put back together I still had the same issue. So I loosened the brass fitting on the fuel line on the tank and wham! That was it. I tightened it down to far and it wasn't letting enough fuel in. Hasn't leaked and has worked perfect ever since!

[fishnjim]

I can't speak for what the factory was thinking and these are the few cars that had it this way, bowl up, ie, upside down in my view.  Earlier no, later no.   What I believe is they screwed up and it wouldn't fit in standard orientation with the parts they had.   To me that's a better more rational explanation of how things worked back then.   It was "corrected" later with the engine upgrade and subjected to much the same heat, which suggests it wasn't "right" during that period.   That one is still debated, but majority rule.
As to A/C cars, some of those filters are three way*.   The top port(bowl down) goes to the return line to the gas tank.   One way of solving the vapor lock problem, change filter to A/C type, vent the vapor back to tank.  Most of the tanks have the port for the return line as they had to service both options.  As an old draw racer, you made a "cool can" that the gas line was coiled in, and you filled with ice.   
But that A/C filter's not "original to car" on a non A/C but you're not using original gasoline either!   One for the judges.
* - rare and hard to find but out there.
Personally I see no problem with a good heat shield sheath over the line and/or repositioning the filter off the engine.   They were used on the wires running over the engine and the choke furnace tube on some.   It comes in all sizes and a few colors.   The only problem with an insulation solution is, if it does get hot, it'll take longer to cool off as well.   Some other brand cars had a metal shield by the fuel pump, to prevent heat transfer much like a spark plug shield.