300zx retrim using the Z Centre Katzkins leather kits

This is my first attempt at upholstery so happy to be corrected by you experts out there!

Using this kit you can get a high quality finish at a reasonable price. The biggest problem was no FAQ or Instructions !!

Tools etc
1. Circlip pliers that open outwards. These are hand and knuckle skin savers !!! This tool makes the removal of the copper 'hog-rings' so much easier. 2. Ordinary pliers, long nose pliers, wire cutters (for the cable ties), various screw drivers, bradle, a small socket set or adjustable spanner. 3. Hundreds of cable ties 4. 1/2" & 1" foam padding
Seat Base
There are different shaped 300ZX seats as you can see from the foam pictures: 1. Series 1 cloth. 2. Series 1 or 2 leather. This seat also has the optional heated seats Unfortunately the Zcentre kit is made for replacing the cloth seats. However with some small modifications a good fit can be achieved for both types.
Start by removing the passenger seat (4 bolts) so at least you can drive the car whilst the retrim is underway. However, if your drivers bolster foam is badly worn you might want to retrim both seats at the same time because you can swap the passenger seat bolster foam with the drivers bolster as they are inter-changeable. Next remove the back rest from the seat by undoing the plastic cover and then the retaining clips circled in red. Also undo any electric cables / clips so the backrest and seat can be separated. Then remove the plastic / rubber reclining seat stop.
This series of photos shows the rough location of the many lower 'hog- rings' that need to be removed before the old seat cover is released.
Once the lower 'hog-rings' have been removed, with a bit of effort, you can peel back the old leather/cloth cover to reveal further 'hog-rings' to be removed. These secure the cover to the top of the seat.
Finally there is a length of plastic edging located in a few metal slots. If it is hard to remove use a screwdriver to prise open the slots.
Next we need to prepare the new seat cover. The first picture shows the difference between the new cover and a Series 1 & 2 leather cover. The two red rings highlight where the kit has two fixing sleeves missing. These need to be carefully removed from the old seats and stitched in the same position on the new seats. These fixing sleeves hold the wire reinforcing rods used to secure the seat covers. Do not throw away your old covers without removing the two sleeves mentioned above and more importantly remove the wire rods as these need to be inserted in the new seat covers. The last picture shows the modifications I made. 1. Is the transfer of the old sleeve. 2. Is to tighten the seat cover to prevent 'bagging'. The wire rod sleeves of the new covers are generally much larger so I introduced another line of stitching to reduce the size.
These two pictures show the insertion of cable ties (top & bottom) to replace the 'hog-rings' prior to attaching the new cover. The two red circles on both pictures show that I have added an extra cable tie to both sides at the back to enable a tighter fit.
Here I have inserted the new cover in the metal slot mentioned earlier and have started to align the new seat cover with the cable ties. Make sure the cable ties are secured round the back of the wire reinforcing rods. Use a bradle to make the holes for the cable ties in the appropriate place. A strong wire coat hanger can be used to replace or extend any of the wire rods.
This shows that when I first finished the seat it looked 'baggy'. It has to be said the Zcentre covers are slightly larger than the originals but you can use old foam from the back of the original seat covers or buy some 1/2" sheets for odd bits of padding. For the seat bases I used 1" foam inserts, similar to the original foam density. The seat foam edges should be chamfered (45 degree) with a pair of scissors to give a smooth fit. 'Just' complete fixing all the cable ties and your done.
Seat Back
The red rings highlight where the head rest release silver clip is located. A real pain to find. A plastic push-fit cover has also been removed in this picture.
I am assuming you are now an expert at finding and removing 'hog-rings'. These couple of pics show where you should start removing them at the bottom of the back rest.
Removing the centre cushion needs further 'hog-rings' to be removed.
Next the two ends of the zip fastener need to be located. These are stuffed down the back of the seat but with a bit of effort they can be prised out. The ends are protected with some grey tape which hangs on for dear life. Unzip the front. The remaining back and bolsters can be recovered by undoing loads more 'hog-rings'. The only difference between passenger and drivers seat is the lumber support controls. These are secured by metal clips hidden behind the controls. Do not try to remove the seat tilting controls as the cloth / leather is stretched behind them and can be prised away with a screw driver.
To remove the centre cushion cloth / leather cover from the foam remove the, you guessed it, 'hog-rings' from the front and back of the foam.
As they say in all good manuals you need to 'reverse the process to complete'. I found that by fixing the new seat back cover in place with the cable ties before you cut any holes for the seat controls etc. gave the best fit. One last word on the headrests...it appears at first that they will not fit in the new covers. Eventually they do....it takes at least two people and a lot of swearing.
Finished Interior
Thanks to Stuart (SMW1) and Luke (Zcentre) for encouragement and their advice.