I'm fitting a shower in my home and i want a good 9.5kw - 10.5kw which will need a 45amp supply. I have 2 spare slots on my CU. My CU is a Tenby. The slots read as follow from Left to Right: Slot1 - Empty, Slot2 - Empty, Slot3 - B32 Sockets, Slot4 - B32 Sockets, Slot5 - B32 Cooker, then an 80a 30ma test switch. Slot6 - B6 Alarm, Slot7 - B6 Smoke Alarms, Slot8 - B6 Lights Up, Slot9 - B6 Lights Dn, Slot10 - B16 Emmersion, then the main power switch running at 100a. I,m competent enough to fit the MCB but do you honestly think its a job for a QUALIFIED electrician?