The gauges that were in the boat were 2 1/8" and mine are 2 5/8", so I had to enlarge the holes.
I backed out the holes with a board, so that I could get a centering hole. I used a 2 1/8" hole saw and used the arbor drill bit to drill a center hole. I then chucked up a 2 5/8" hole saw and used the centering hole, and cut the new hole.










I am running a calgo steering and I have 6" post, but I would like the post to be a little longer.
I have a billet steering helm bezel that went to an obsolete Detmar rack system. The shaft hole is threaded, but is an exact fit to the calgo steering shaft.



I am going to use that as the base,or bezel, for the 6" post, which would give me a 8 1/2" inch post, plus the wheel, for a total of
11".
The Calgo post has 3 bolt holes on the bottom that bolts to the dash, in a fixed position and the calgo slides into the post and You can adjust to what ever length post you want. All I really need to do to make it work is drill the bezel to the same bolt pattern as the post, use threaded rod from the post ,thru the bezel, thru the dash and backup plate and nylocks behind the dash. the bezel even has room to put nuts behind to actually bolt the two pieces together before going thru the dash.
Of course one problem is that the two pieces are not the same color and I would probably want to get them coated.


I drilled the base to match the post bolt pattern.




The base was a billet helm base for a for an obsolete Detmar rack steering. It is threaded for the shaft, which the hole is the right diameter for the calgo shaft. The only problem is that it has a collar or seat, at the top , which is smaller than the shaft hole.
So I chucked up a burr in the drill press and milled it off. Not the prettiest milling job, but it did the trick.



my ugly drilling job, because my cheap azz drill press sux ass!




And here is how it all stacks up.









I need to make some longer studs from threaded rod, to go all the way thru the dash, but you get the idea.


I installed The base of the calgo steering post on the dash. I used a transfer punch to mark the holes on the dash.



I thru bolted the post to the dash, using ss threaded rod and ss nylocks on the back side.
I reinstalled the gauges, installed the switches and ignition switch. The dash is basically done.