[T2] '74 Westy, ground

[Squid]

Hi, I am in the process of installing a Dakota Digital  oil temp, and cht gauge as well as an oil pressure gauge onto my dash.  Have the gauge 'layout' in place, and wires connected , but the gauges need a ground!  Can I just tap in to any exposed sheet metal in the 'cab' area, since ground strap out back does the same, or is there a ground place, I should tap into up front..but I don't know where?
Cheers
Scoggy