Because of the large size of this eBook file, here are a few options for downloading on to your iPad:

1) Email the file to yourself and open using iBooks or Bluefire. (File size may be an issue for this option too, but it would be the easiest way.)

2) Download to your computer, then load the file to your iPad using iTunes.

3) Load the file using Dropbox. For this option, you would first need a Dropbox account set up and have the Dropbox app downloaded on your iPad. (These are both free).  Upload the file to Dropbox on your computer, then open the app on your iPad and once it is downloaded open in iBooks or Bluefire.