roof rack

I found a great deal on an old (but excellent condition) Yakima roof rack/bike rack combo. It utilizes the old SST tower system with Y clips. Does anyone know which Y clips would be compatible with the bolt roof? Yakima stopped listing vehicle compatibility when they stopped producing the SST...

I'm making a DIY roof rack. Does anyone know the size of bolts for the roof rails? I've tried metric and SAE and can't find anything that fits. I might be using the wrong thread type. I've tried course metric and fine SAE.