1954 GMC..... Shark Gauges Fit?

[69l46vert]

Hi All,
Too cold here to do much so I've been considering what parts to order for my 54 GMC build. Have been looking at Shark gauges, mech. speedo and the rest are electric. They are described as 3 3/8 for the speedo and tach, and 2 1/6 for the other four gauges. My worry is that they may not fit the stock openings. The measurements seem really close but because of the way they mount from the back I'm not sure how they will fit the holes. Anybody out there bought these gauges for your GMC and did they fit the holes ok?

Here's a link to the set I'm considering. Thanks for any help or guidance.

http://www.store.dolphingauges.com/v...p?productid=92