Just wanted to report another success and thank Adibee for the measurements and instructions, Bomar for the original post . I will give my account, hopefully will be helpful for some.
I never did this before but did have the tools to cut the metal and drill holes.
for the metal pieces needed to hold the bolts, I got a 2.5m piece of 20mmx4mm metal from B&Q for around £8.50 (couldn't bother to order and wait for it to turn up), cut them into 2x 120mm pieces and 2x60mm pieces. drilled 2x 7mm holes 48mm apart from the centre (or 96mm apart) and one in the centre. ( I did a 7mm hole and squared it using a file as per the original post by Adibee but found you can probably get away with 6.5mm holes. I may have had a smaller bolt so Check the coach bolt that comes with the 3033 fitting kit as there may be differences in sizes). Then another 3x 7mm holes on the 60mm piece 35mm apart (17.5mm from the centre).
The gutter trim on the car has a plastic trim at the rear end which comes off if you pry it off with a small screw driver. then there are 4 more clips to completely unclip the trim. 2 clips/retainers are about 10cms away from either end and the other 2 are where the screws are in the pictures. Or simply pry along and you cant miss them. I would advise not to try and slide the trim off from the front as it is a bit fiddly to put it back. you don't need to have the trim off completely to do this.
Now you fit the plates to retain the coach bolts for the fitting kit, drill a 8mm or 9mm hole where you want the bolt to come out through. put the trims back once all the bolts are retained with the metal pieces and nylock nuts.
Took me around 4hrs to finish but I never worked with metal before and I decided to paint the metal pieces 🤪
I used 753 foot pack and 123cm aerobars. Looks nice on, no wind noise.
hope this helps someone. If I have missed anything, please ask. I will add some pictures soon.
