Having looked everywhere for a cheap, secure GPS mount, I sat in the garage, staring stupidly at Lolly's speedometer. I turned the suction cup mount over and over in my hands....

 

I've been mounting mine on the Speedo too, when I've needed to use it, though I put it further left than what you do, but come on...do you really need a "Special" GPS Mount other than what came with your Unit you've already paid $200+ for??!!

 

haha - jmo, but you get what you pay for.

 

I cover the gas "gauge" with my suction cup....just be careful not to press to hard on the plastic.

 

This is how mine is mounted, didn't want to lose view of ScanGauge:

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Would be easy to mount it much higher, if you did not have the ScanGauge.

The Power (& traffic antenna) cable was easy to completely hide behind the Tach.

I used the 'Sticky' Dash Mount which is 'Articulated' by both the Nuvi Cradle Ball

and the second ball (w/tension ****) at base of the mount.

I did not expect to fit the Wide Screen Nuvi 755 in that location at all, nevermind w/ScanGauge.

It was $8.10 from AMAZON.COM I tried the Garmin Suction Cup mount on my Speedometer,
but found that when I tilted it toward me, it popped off the Ball.

SEMSONS.com sells a Suction Cup Mount with the same 'Double-Ball' articulation for $5.99
which would allow much more 'adjustment' than the Garmin mount on your windshield or speedo.