How the Serpent is using the bearings is their design and can not be used on a Evolva. Just use the bearings as mentioned in your manual.
About the spacers it is all about the gap and endplay. Gap = 0.7mm and endplay as less as possible but still something visable, in numbers you do need 0.1~0.2mm
Just follow this: http://www.youtube.com/watch?v=7wjogF57xpo
But only about the gap and endplay.