no its really simple
to remove carefully leaver it off from the top with 2 screw drivers. like taking a tyre off a bike
once its off part the lock so you can put it back later
repair and check you door lock etc and replace the boot (seal)
if you look at the plastic ring and put it back on the same way round it came off there are 2 indents where it locks together where a tool is used to tighten it up. put it on and lock it on the as far as you can by hand then using 2 screw drivers, hold the heads of the drivers in one hand. put the tips of the drivers in each slot either side of the band lock. then with your free hand squeeze the drivers together to tighten
Dave