Tachometer install on steering column

Morning, Ladies and Gents.......

Finally got my tachometer issues all worked out. Ended up purchasing a S/W tach off of ebay. Its a retro-look S/W with modern internals and no sender is needed. Here's a picture :

I could use the standard mount...which is, of course, the hose clamp around the steering column, but I would prefer a little cleaner install.The chrome cup the tach fits in has the usual curved area the clamp fits over/thru but it also has three holes in which a screw could be inserted.

My question is :

Exactly what goes down through the steering column and if I use, say 1/2" self tapping screws......am I in danger of screwing something up. My understanding is the steering column is simply a hollow shaft with a long 1/2" diameter shaft in the center. I would think there is a fair amount of empty space around that shaft so the small screws would not interfere with anything..kinda similar to the grounding strap for the signal-stat blinker assembly, but I'm not sure.......Any suggestions ?

 

There is some free space in the tube. As long as you keep it short you should be OK. It would definitely be a clean look.

 

Drop to 1/4" screws.

 

When i had mine appart there is about 1/4 in clearance, But pull the horn contact brush off the bottom to double check.

 

No reason for screws to be much longer than the tube's wall thickness.