Just done this to a Supra, it made a huge improvement in the car's spark and general running note at idle - much much smoother, and for a total spend of less than £35 for 6 new coilpack connectors it is must do job if your connectors are past their best!!
If you follow Ian's instructions you'll be surprised how easy it is to do... I found that upon removal that in most of the connectors the white plastic centres were breaking up and that also the rear of the grey plastic casing was very brittle... I replaced all the plastic casings and white centres as per Ian's instructions. However I found the easiest way to remove the metal pins was simply to "pinch" the wire(s) at the rear of the connector and they would simply pull out as the plastic was brittle enough for them to come out quite easily. If the pins don't come out after a gentle pull do not force them and revert to Ian's method, as some casings will be in better condition than others.
If after you have removed the first part of the housing and the white plastic centres you get really stuck in removing the pins another method that worked for me was to use a pair of pliars to gently "crack" open the remainder of the casing/housing, (as it is to be replaced with a new one anyway), this way ensures that you do not pull the actual wiring away from the two metal pins... the pins then simply "click" back into the new casing very easily...