A tip for measuring the length of cable is to use a piece of string and route it roughly where the leads would go, measure from the top of the plug boot to the top of the other boot, where the cable goes into the boot. I can work out the extra bits that go into the boots.
I will have to check but I think the screw connectors on the end of the leads would be compatible with your existing boots if you wanted to re-use them. The boots that I would supply with the leads would not be OE, but just as good........I would say that though wouldn't I!
Our supplier for some of the boots also supplies Ford but has to grind the Ford logo off every one that he supplies us!!!!!!