Inlet ducting
One of the older kits that I'm still slowly building as a background project (Mig 15) has each side's inlet duct provided in halves (upper & lower) which you must join together before fitting. This leaves some room for error since each modeller may join the parts slightly differently - because you have to sand the Mig's parts slightly to get them to join to each other properly, and doing that may affect the fit of the completed part to the inlet on the fuselage.
I'm happy to report that the approach taken in the Super Bandit makes this whole process much simpler, and makes it pretty much impossible to have a poor fit. This is because each side's inlet ducting is provided as a complete unit (rather than in halves), and consequently the fit of the duct to the inlet on the fuselage is pretty much guaranteed.
All that you need to do is get rid of any mold flash, and file / sand / grind gently on the areas to be joined until they slip together perfectly.
I started by cleaning up the lip on the duct, as shown below. Note that I'm being lazy and using a grinding stone to remove the primer from the lip, as well as make a very slight bevel to ease parts fit. If you do this too (rather than using sandpaper or a small file) be sure to take it gently... the material is fairly thin and does not need much adjustment at all. In my case, I have a Minicraft tool that has infinite speed control, and I'm running it at maybe 200 rpm. If in doubt, play safe and do it by hand.