Never heard of FK.
However keep in mind with a drop of circa 40mm you will spend about another £1000.00 getting the geometry and ball joint angles sorted out if you fit decent quality correction arms and ball joints.
A link to the springs may help in identifying them.
And also welcome to the forum.
Alex.
to the forum Craig.
I am just up the road in Perth, so if you want to swing buy on your test drive, I would be more than happy to give it the once over for you.
Alex.