Needle nose pliers
17mm wrench (and a 17mm ratchet if preferred)
2 x tierod ends
2 x castle nuts
2 x split/cotter pins
(the castle nuts + pins come with new tierods from MX5parts.co.uk)
1) Jack up one side of the car, put on jack stand and remove wheel.
2) WD-40 the castle nut and tierod lock nut.
3) Remove the old split pin from castle nut with needle nose pliers.
4) Undo 17mm castle nut.
Upside down Castle
Upside down Castle nut
2) Leave the ball joint shaft where it is(with the upside down castle nut in place) and put a 12mm spanner on the steering arm bracing it against the lower A-arm.
3) Paint a mark with typex or similar on the lock nut + threads so you can line them up again later.
4) Use the 17mm wrench to undo the tierod lock nut a half turn (turning against the braced 12mm wrench).
5) Remove the upside down castle nut and spin off the tierod end (count the number of turns it takes to remove it).
If the ball joint shaft spins when removing the castle nut, pull off the rubber boot a little and clamp pliers on the shaft.
old vs new Locknut loosened
old vs new
7) Push the shaft of the ball joint into the stub and finger tighten the castle nut on it.
8) Rebrace the steering arm with the 12mm and retighten the 17mm lock nut (its also good to count the number of threads up to the locknut to ensure you�ve got it aligned correctly as well as using your paint marks).
9) Tighten down the castle nut until the ball joint shaft seats correctly, if the castle nut doesn�t line up with the holes in the shaft for the split pin, tighten a little more.
10) Insert and split the cotter/split pin.
11) Refit wheel, remove jack stand and lower car.
12) Do the other side ;-)