The primary way to reduce your heart rate is to reduce the pace. The other way is to improve the technique, which will increase the efficiency, however this is not easy and the result is not likely to be dramatic.
I am convinced your problem is different, though.
Recommendations for running heart rate zones are often misleading for a particular individual, as they are based on statistical averages, but individual zones differ a lot. Zones based on % of max vary a lot in particular, what is much more reliable are zones based on % of lactate threshold.
There are two articles dealing with the subject I have found quite useful:
Another article about settings the zones can be found at Training Peaks blog, with less explanation than the two articles quoted above, but with easy to follow instructions.
Both me and a friend of mine had the same experience, as our LT is way above average and we were mostly unable to use any HR zone based training advice until we switched to LT based zones.
The most common way for a hobby athlete to determine the Lactate Threshold is so called "field test" (following quote is from the Training Peaks blog article):
To find your LTHR do a 30-minute time trial all by yourself (no training partners and not in a race). Again, it should be done as if it was a race for the entire 30 minutes. But at 10 minutes into the test, click the lap button on your heart rate monitor. When done, look to see what your average heart rate was for the last 20 minutes. That number is an approximation of your LTHR.