Here's the one I built.
I now have a self igniting torch head mounted under the ramp, that way I can use a 5lb. tank with a 4 foot hose for more consistent flame and less refilling the 1 pounders.
That's the main draw back with this set up ,once the small tanks get to half fill or below you get flame temp variance due to changing pressure levels.
I keep 12-15 old brass for set up each time to verify, then it's just load them on the ramp one at a time and run it.
I have a plan to modify a longer ramp to make it auto feed some time in the future.