According the Havoc II Pilot's Notes, the two groups of four gauges are the port and starboard engine gauge units.
A read through the pilot's notes provides some more specific info.
Lower right hand gauge - air intake thermometers (carb heat) ref. Section 1, para 25.
Top right hand gauge - fuel pressure gauges ref. Section 1, para 31.
A "Telegon Instrument System" is mentioned in Section 1, para 37 which includes boost gauges, fuel pressure gauges, air intake temperature gauges, oil pressure gauges, and oil temperature gauges, as well as the flap and undercarriage indicators. All of these are run electrically, and turned on by a single switch. Since the two groups of four gauges are described as a "gauge unit" and the two gauges known to be part of the units are also listed as part of the Telegon Instrument System, it is almost certain that the other two gauges in each unit are the oil temperature and oil pressure gauges. The other gauges listed as part of the Telegon Instrument System are shown in the diagrams in other places. At a guess I'd say that the top left gauge is oil pressure and the bottom left gauge is oil temperature, but I can't tell for sure.
Perhaps looking up Telegon Instrument System might yield some more usable pictures.