SBC intake manifold question.

[69427]

Help a BB guy out here, please. On several sbc intake manifolds I see a couple vertical threaded holes (3/8" thread) on the center left side of the manifold. I'm drawing a blank regarding the reason they're there. Anybody have an answer for me?

Thanks,
Mike

 

[COLE SWEAT]

I’ve seen throttle linkage brackets mounted there on stock manifolds