<VV> 3-pt seat belts in 69 coupe

[David S Malcolm]

Evening all
I've recently acquired a nice running 1969 coupe and one thing I'd like 
to do if possible is mount the more modern 3 pt retracting belts. The 
car of course does have the factory mount on the roof for the separate 
shoulder belt but it rather far back.
Does anyone have any ideas about this or if its possible without welding 
additional mounting points.
thanks
David Malcolm