Had an issue with belt location when first got my van a couple of years ago. It had no rear belts and with 2 kids was THE first thing I got sorted after some head scratching and searching on here...which was very helpful if only to make me realise what wouldn't work in my van.
I have a 3/4 R&R bed and have 2 3pt belts and a centre lap strap. I have fitted both the reel and anchored end under the seat, looping THE bebbing up and over the seat back. You can use the mid point guide slit bit in the kit to fit to the rear face of the seat back to ensure that the belt stays at THE correct shoulder position. I used the marked positions for the receivers and drilled the angled engine section and wheel arch to fit the reinforcing plates for the reel and anchored end, and jobs a good-un. This has also been through an MOT and the only comment was that the belt sometimes didn't reel in as quickly as it should but a minor repositioning of the guide onteh seat rear solved this.
Also, don't know if it's been mentioned before, but a seat that is not secured to the frame (ie the foam to the R&R bed) is an MOT failure as the whole lot could slide under the belt in a severe head on.
Hope that this information helps. I can take pictures if you want and (try) to post them. Have fun working it out
![OK! :ok](./images/smilies/ok.gif)
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