We tackled this problem last summer. Our solution was to purchase one of these:
http://www.harborfreight.com/hydraul...ool-66150.html
We also only use uninsulated terminals, as the hydraulic crimper destroys the plastic insulation. We then use either heat shrink or liquid tape to insulate and strain relieve the wire to terminal connection.
The first terminal I crimped with this thing blew my mind. The terminal and wire are so tightly fused, they are indistinguishable. Even the seam where the terminal overlaps is just gone. Connections made with this tool now have the pull strength of the wire itself.