the method on the video looks sound, you'll have to drill the hole in the side of the funnel yourself, alternatively there's a page on it here pyroguide black match this method is fine for 4/5 foot lengths, i use it myself.
although blackmatch itself isn't an ideal substitute for visco as the flame can jump along the length of the fuse giving a unpredictable burn rate, the main use to blackmatch is the the production of quickmatch which incredibly fast burning, ideal when you want to light a succession of fireworks at the same time
talking about black match, get your self a used up shower sealant/ no more nails type of tube with the nozzle, cut the nozzle to the diameter you want for your black match, pull the kn03 soaked string a little bit through the whole, and then pour in a thick slurry of bp, then just pull the string through and you will get consistent black match, i make 12 meters at a time with it, (make 6 then cut it then make another 6, i just put a few screws in a bed slat and ran it length ways up and down, works a treat
