Question on installing H60 bracket in 250D

Hello Corsair enthusiasts, I will be purchasing a Hydro Series H60:soon to install in my 250D. It's a bit cramped at the front because the RM550 cables are a bit stiff. Is it easy to take out the PSU but leave the cables that are connected to the mobo and GPU, and then install the backplate from underneath. Or will I have to go through the hassle of removing the mobo, GPU and optical drive?

Answers are appreciated.