Looks fairley clean. Just try to get the majority of think stuff out. After a few 1000km's, the inside will be just as dirty when you first got it from all the clutch dust.
So your saying that doing over 200km/h is less illegal than a blow off valve or exhaust? I'm sure the sound of an exhaust or blow off valve is less harmful to a persons well being than hitting a pedestrian at over 100km/h.
Other alternative is to remove the filler neck, remove all fuel vapour and film from the filler neck. Then weld the fuel restrictor to the filler neck. Thats the proper way to do it.