[FC] Rampy front seat center seat belt

[mhicks130 at cox.net]

I would like to put a center seat belt in the front seat of my rampside.  It already has the outer 2 belts installed.  Can I use the inner attach points to attach the center belt??  Or should I drill 2 new holes a bit inboard of them?  Our 9 year old son will have to sit in the middle when the 3 of us travel in the rampy and he needs to be restrained, so to speak.   

mike