I'm just finishing up installing a remanned np208 in my '86 K5. there is a hole above the speedo drive that appears to be threaded. What is it?

 

Speedo cable retaining bolt perhaps? There typically is a clip that slides into two slots on the nose of the speedo cable end and that clip gets bolted to the side of the transfer case tail housing.

If that's not it, maybe a picture would help...?

 

Thanks for the response, if it's a support for the cable it would be a pretty large
bracket and there is no evidence of it. Is there a vent requirement (nipple and hose, maybe)? If not I'll just plug it and go on. The next challenge is the broken
bolt at the bell housing for the long support arm, got me scratchin my head again.

 

Can you take a picture and post it?

 

here's a closeup

 

My first guess is a hole for a bolt with a chain attached to help get it in or out... I've never seen a hole like that on mine, but mine's never been out from under the truck either lol.

 

The hole I was talking about is the one that is right near the speedo bore. The one towards the top of the picture you posted... Not sure. I wouldn't get too worried about it if it doesn't leak out any fluid. Just install it like your old one was installed and call it a day.

 

Thanks to all, but now my daughter wants a Blazer trimmed in pink.

 

Haha. It was super easy and cheap to do.

How old is your daughter?