RE: Ultimate engine test stand
Use some pillow blocks and an axle for the engine mount so you can measure torque as well. Horsepower as well as thrust can be measured. Also add an airspeed pitot for the slipstream velocity for the ultimate propeller dyno. The only instrument you mentioned that would have least value would be the temp gage. I say this because these small engines cannot be damaged by tuning lean of peak like a much larger one will.