At this point I’ve installed most bolt-ons to my rs5. By far my least favorite was the front springs and a close second was the rear sway bar. The springs sucked because there was a lot to unbolt and little room. The rear sway bar because of the tiny amount of room to tighten things up given the huge lower control arm. Oh and I bashed my head on the lowered exhaust since I forgot to avoid it as I rolled back.
Not necessarily a Bolt on since they require engine removal but the headers are a real pain. I think it’s the Drivers side which is the worse to get all of the nuts on and impossible to get a socket on all of them to get them torqued.
With that said, I’ve now removed 2 RS5 engines and installed 1, getting ready to install another, hopefully the last, it’s a difficult install too 
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