ive done a few with good success, the problem is what dave was talking about, it isnt straight to push out or refit, its on an angle to the wishbone surface, but if you take some time its easy.
ive just had an advisory on mine (driverside) it was torn, the tester said if its showing signs of loosing grease then its a fail, mine wasnt so he passed it.
i just sourced some cheap boots from the local factors to fit if the joint is ok once stripped and checked.
the problem seems to be that the individual components to the wishbone, the wishbone itself, the 2 mounting rubber bushes and the balljoint, if bought seperately cost a bloody fortune. the whole thing complete from mazda is far lower in price, and should last years.

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