for the display/controller - same place you tee most things into - the vacuum hose coming from the top of the BOV, leading to to the inlet. you tee off here for boost gauges too. i've got several 'tee's here and it all works fine
theres a guide on here for 'Fitting a Defi Boost Gauge', it shows the tee point there.
for the solenoid - one off the actuator, and one somewhere along the intercooler system. i've got mine coming off the first section after the intercooler. but as far as i'm aware it doesnt make a difference. i just chose a cooler section in my attempts to keep temperatures down and make it last longer lol