You are limited in the cams you can get because pre 98 Zetecs have hydraulic lifters.
So you can't use any of the cams meant for a Focus, since they use mechanical lifters (unless you want to do a head swap).
I plan on using Kent cams myself, but they are expensive, over $300 per cam.
What cams to use depend on your mods and what kind and where you want your power band.
To complement simple bolt-on mods, I would go stage 1 with power from 2k to 5k rpms.
Anything more aggresive would be a waste.
If you plan on doing some headwork, then stage 2.
With cams you should install a set of cam gears, this will allow optimal tuning.
As for the physical process for swapping cams, its easy, just like changing the cam gears.
Just involves a few extra bolts to be removed and pulling the cams out.
