Bad Injector?

Just got my engine back together and running. It isnt a stock engine by any means. Renix block and head w/ porting, 99 intake, 94 throttle body with renix tps, 94 fuel rail, and ford 460 injectors which i pulled out of a junker. Anyways this thing has been sitting for a while. Drained the tank by hot wiring the fuel pump and draining before the fuel filter. Put 10 gallons of shell premium in it with some sea foam and lucas injector cleaner. It ran great for a while and during warm up. Then i started it the next day and took her for a test drive and it started missing. Pulled plug wires 1 at a time and the miss was in cylinder 6. Swapped wires and plugs and still in that specific cylinder. It does have spark but looks a little weak. Pulled the plug and started her, great compression in cylinder 6, the plug was dry and i couldnt feel a mist of fuel shooting out. any ideas? is there a way to test the injector?

Switch it to a different cylinder.

If the injectors have been sitting for a while, run some BG44K in the tank.

I dont think i mentioned this is also a 4.6 stroker too... now, i did never change the fuel filter or the regulator but when its started i have pushed the valve on the rail and it seems there is plenty pressure in the fuel rail. i was just getting ready to swap the injector out with a spare when i went to bleed the fuel and noticed there wasn't any pressure at all after i shut it off. i think my other jeep kept its pressure. i did have an older fuel rail though. is this normal?

Oh and is it possible for low pressure to only effect cylinder 6 cause its at the end of the line? where do i find bg44k and who makes it

BG44K is usually carried by shops. Sometimes hard to find in stores.

Gasoline (liquid) is basically non-compressable, therefore the pressure at the ends is essentially the same as the middle.