yeah thats where i was intending to put them but they are too big. i have come up with another solution........
The landy used to be a truck cab, its now going to be a rag top. So to fit the top point of the seatbelt im going to remove the box section part inside the truck cab and bolt it on to the edge of the tub. i will then weld a couple of braces between the two sections. The lower part of the seatbelt can then be bolted at the side of the seat box.