Im starting a ph dark angles army and i was going to convert the knee gaurds of the normal legs to the mk4 legs and was wondering if anyone could help me out. :)

well the best I've seen is to use thhe one piece greave leg and carve out the kneedpad with a craft knife.
Meaning where the kneepad get narrower at top cut a line across it
kind of like this first marine on left

http://us.games-workshop.com/games/40k/dar...cters/borer.htm

Thanks eisenhorn ill give it a try.