Hi Tom
As you can see from the thread mentioned by James i have fitted these belts, they look fabulous but do require a bit of modification to make them work.
The reel can either go under the parcel shelf or behind the side cover....i fitted behind the side cover as it was the least intrusive and easier method of fitting these particular reels as they are slightly larger than other reels.
When fitting the shoulder height guide which the belt runs through.
.
1) You could use the existing (if fitted) low shoulder mounts behind the side covers( which make the belt twist over your shoulder)
2) or follow mercedes higher mount fitting instructions, as i did, but only do this if your car is in for work as it involves grinding and welding .
3) or follow James easier method, slightly less intrusive , slightly lower, shoulder mounting but has the bonus of requiring no welding..
Best of luck which ever way you go but if you decide to get these belts be aware that they are not an easy fit but with a bit of modification they can look fabulous.
Cannot show finished pictures yet as car is still months away from interior fit up....millions of jobs to do first but when stripping the car i cut the side cover slots, drilled the 2 holes and fitted the higher shoulder seatbelt anchor point, the belts worked and ran just fine.
Dave