I believe the stock size is 3.25"
Most go for the mini gage ~2"

Ha ha, oh dang you caught me off guard with that one.

Im wondering if the 3-3/8" (85mm) would fit or be too tight.  Im adding some Speedo/Tachs to my lineup that might interest some here.  There has been lots of posts about what tachs to use and this might fit the bill for a few people.

And per previous requests I had it made with a black back and trip-meter.  It comes with the same color options as my other ones. Polished or black stainless bezel and white or black face.

But Im not sure the depth would work in the stock LS650 placement.  The GPS attachment on the back will stick out a bit.  The straight connector will need about 3"(75mm) of depth, or use the 90 degree connector and be at about 2-3/8" (60mm). From the mounting face.