gas gauges RV-6A

Just flew off test time on newly OH engine and looking good! During work session replaced both tank sending units as rt side was bad. Now neither work well. This is equipment as supplied by Van's. What do you do to check the gauges? Thanks for any ideas.
Dick Seiders

see notes on http://vansaircraft.com/pdf/Gauge_Install.pdf

thanks, Vern. See you Sat. at the RV flyin
Dick