Is there something I can do to better match these two BMP180s to each other?
Unless you have installed your second sensor in some kind of high-pressure chamber, you are not getting good readings from it.
Either your I2C connection or your calculation is messed up somewhere.
It is normal for those calibration numbers to be quite different between different individual sensors. That isn't your problem.
My suggestion would be to set up your arduino for one sensor. Test one. And then test the other one. You should get very similar readings.
There is a lot of completely bogus code floating around the internet for those sensors. It is not easy to tell the genuine ones from the bogus ones.
That ridiculous algorithm which they use, to transform the raw readings into temperature and pressure, is very sensitive to coding mistakes.