Seat belts

I'm trying to put seat belts in my Sprite. Problem is the PO (DPO in this
case) put new rockers in but there is no threaded "nut" on the rocker side
for the seat belts. Any ideas on how and where to mount this side? My only
thought so far is to drill through the floor.
 
Herby
64 MK II Sprite - HRBYTOY (under construction/de-construction)
62 MK II Sprite - HRBYTOY2? (My new driver)
billh@aaai.com 
www.herbytoys.com
 
(P.S. thanks for the info on my Weber problem. I'm going work on that this
week)