Not hard at all. The bolt pattern is the same as the original. Assuming you have the cast aluminum bracket, you will need to cut a section out and create a pocket on the back side for the new pump to fit as it has a bulge in it. The pulley can also be re-used and it should line up the same as the original. The return line is a snap as it just slips over the nipple o the new housing and is the same diameter as the original.
The only difficulty is the supply line. I recommend using a -6 AN adapter, but there are other adapters that may also work. If you use an AN style adapter you will need to fabricate your own hose, but it's not really that hard. Make sure you buy hose that is pressure rated for power steering, and after assembling the end, clean it out real good so no debris gets into your system. The other end could be swaged on at an automotive store that makes hoses so that it mates with the factory control valve or perhaps you could find an AN adapter for that end as well. The nice thing about the AN hoses is that you can disconnect them and re-use them indefinitely so long as you don't over tighten them. They also don't leak.