Transverse rear seats in a SWB Series

Hi!
I've got a Series 2 that I've made into a crew cab of sorts using a defender smooth roof, a series truck cab back panel and Defender side panels cut to fit. From time to time I need to take my children out in it and I'd much rather they were forward facing. Looking at the measurements I think a 3 seater bench fron the rear of a 110 would fit straight across and I could use the belt mounting points in the truck cab back to fit to top part of three point belts. Has anybody done this before to give forward facing seats in the rear of a hard top? and does anyone have a 3 man bench seat from the rear of a 110 that needs a good home?
Thanks in advance

It's not the seat mounting that's the problem, it's the seat belts. Have you considered putting the bench facing rearwards?

Rear facing seats would be safer but getting in and out would mean climbing over the bench seat. I thought about using the truck cab upper seat belt mounts and the lowers could be attached to a large plate under the floor. My other thought was to fit the roll bar hoop that I have at the veary rear of the cab with the seat in front and three or four point harnesses mounted to that (It's a chassis mounted hoop and will have weld in tubes running forward and then down to the chassis at the front.)

When i gotMy 110 van had a transverse seat across the boxes with the seat belts bolted to plates through the boxes and bolts through the rib halfway down the van sides. My local MOT centre was exceedingly unhappy, he wasn't going to issue an MOT due to the mountings of both seat and belts being to thin aluminium. but I told him it was going to be removed( which it was) so he let it through.