as for the ScanGauge & trip mpg/consumption & range - i would say don't bother....because that feature doesnt really work, its entirely hand calculated & does not seem to pick up any data from the diagnostic port.
yup, velcro is yo' friend
You could use some double sided / 3M body side molding tap - but that would make it considerably
more secure & more difficult to remove.
I got the same mounts (suction cup & "desk top" stand).
I've relocated mine TST monitor twice now.
Did you get the flow thru sensors ? I have the (user replaceable) spin ons. I removed the security covers on mine - as I've grown more comfortable...and without the covers its a lot easier to get them on and off (for ~annual battery changes).
without the security covers i haven't had to use the wrench & where I've had one or two that were tight & spun the battery/cover off i just used some right angled long reach pliers.
here's where i used to have the TST Monitor (before i moved it to place the ScanGauge) -
'04 Haulmark (M42386) 42', 2 slide, 10kw - Pictures
'04 F350 CrewCab Longbed 4x4, 50g aux tank & gear vendors dbl over