You don't want to guess at this.  
You want to call the pump maker and talk to an applications engineer.
He will have charts that will answer your questions.
You do not want to try to do the math yourself based upon what you have in
hand.

A gear pump is a good thing for honey, as it will always produce the same
flow at any given RPM.
I bottle with a gear pump, and it is a joy to have a perfectly repeatable
fill with nothing more than a timer and a footswitch.

But the RPM you will get out of a certain motor depends upon the HP of the
motor and the viscosity of the fluid. You have to select the correct motor
size for the job, or you will either pump too slow, or, if too fast, with
honey, you might to blow a seal on the pump at very high RPMs.  (Honey is
too viscous to "slip", and come around the gear back to the input side of
the pump, see below.)

You can't select the motor size without some math, and you should not have
to do this alone.  The pump vendor should have an applications engineer to
help you out with this.  You only need to tell him a few things.

Because gear pumps can't create a "perfect" vacuum, the total lift
(including pipe friction losses) can't be over about 7.5 PSI, or about
one-half of the atmospheric pressure.  Don't worry about calculating this,
just know the physical dimensions of the tanks, the placement of the pipes,
and so on.  The pump guy will have a cheat-sheet to figure the total lift,
and will tell you if you need to relocate any pipes.
 
Viscosity matters, and honey viscosity varies significantly with
temperature.  The Airborne Honey (NZ) have plotted curves for viscosity vs
temp:  http://www.airborne.co.nz/manufacturing.shtml  The good news here is
that you design for your worst-case (coldest) viscosity, and the motor will
simply have an easier time of it at the lower viscosity if your ambient temp
warms up.  

Warning, the page above uses "poise" to measure viscosity, but everyone else
uses cps or kg / m-s.  So, 1 poise = 100 cps = 0.1 kg / m-s.

So, work out your viscosity at various temps, and you have all the data you
need to have a conversation with the pump applications support engineer.

For any one gear pump, there is an optimal RPM for the combination of
viscosity and the pressure at the pump inlet.
To get that RPM, you need a certain amount of motor horsepower.
More power won't help, it will hurt.  
Less power would be a shame, as you won't pump as much as you could.

A) The most basic curve that the pump maker should provide, is "RPM vs
viscosity" for that pump.  Self-explanatory.

B) The next curve should be the gallons per minute the pump will move at
various RPMs, which is the best you can get from the pump.

C) The next curve is "volumetric efficiency".  This is the "slip" curve.
This tells you how many RPMs you need to add to the RPMs in chart (B)  to
get the net Gallons per minute you need.  Likely with honey, you will have
near-zero slip, due to viscosity.

D) The next chart is Input horsepower, RPMs, and discharge pressure.  This
tells you how many horsepower you need to get the RPMs you want.

E) The last curve should be the "viscous horsepower" curve, which allows you
to add some horsepower to overcome the change in viscosity if things get
colder.  If they have this chart (HP on vertical axis, viscosity on
horizontal, read the RPMs as a result) you can plug in your warmest
viscosity as the "design viscosity", and then use this chart to work out
what to do about the coldest viscosity.  This will take some talking, as the
pump guys are used to talking about pumping oils in winter as the "worst
case", and you are talking about a "worst case" that happens over a much
narrower range of temperatures.  But take the time to run various scenarios
on this chart to see what happens to your HP at different viscosities.

So, now you have a horsepower figure, and you can pick an appropriate motor,
and you are done.

I could go on about pipe-friction and cavitation at fittings, and so on, but
you fell asleep 10 minutes ago, didn't you?  :)

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