So I kept contemplating wheel spacers just for cosmetics..But I bought new tires and went with a little more sidewall and they rub on the control arm bolt when I make a sharp turn so now I actually need them ..I ordered 25mm rear and 20mm front .I was unaware but Ford focus use same wheels as Jaguar,so I ordered spacers for a focus .I was just curious is there anything I need to be aware of when installing..Like torque spec of the bolts on the spacers ,and do you still use the same torque spec on the lugs nuts as I would without spacers..Any maintenance I need to worry about ..Sorry for all the questions couldn't really find much info ...Thanks in advance..

 

Not complicated, as you guessed just do the spacer nuts up to the same torque spec as the wheel nuts which is 125 Nm or 92 ft/lb.
That said I have fitted/removed/refitted spacers on my F-Type many times (same torque spec) and never once used a torque wrench, I just go with RFT every time which works for me.
My only other suggestion is make sure the hub faces where the spacers sit are nice and clean and rust free, same with the mating surfaces on the insides of the wheels.