Engine Over Speed

Hardly matter so long the output speed of gearbox is acceptable to you.It will give more RPM, about 3% higher, is that ok for you?

Your gearbox will certainly heat up to some degree but i think overrunning that gearbox to approximately 4% will not have considerable heat gain and material fatigue, designer usually add up minimal 25% tolerance on any of their design.

However, your pump might have problems, increase of speed is proportional to hydraulic power, definitely the head delivered by that pump will increase. Further increases speed stress more the impellers(cavitation & blade fatigue is probable) and adds up pressure to the casing. Thus, you should look at tolerable speeds of pump, i believe it will be provided on the pump manual or consult your pump provider.

If it is a centrifugal pump, flow will increase by 760/736; discharge pressure will increase by (760/736)²; and power consumed will increase by (770/736)³. If the engine is not stalling, this is most likely no problem.

However, you should be able turn down the governor or fuel rate to get back to 736 rpm, and thereby save some fuel.