Very easy I got some off ebay not really expensive and they worked great I'm a dna fan but to be honest there cushion suk balls in have three pairs and they all do the same $@$* hut any way first you remove the old ones completely there is a little strip that is on the edge that has to be removed once u do that the replacement ones have the same ship on it slide it in the gap from were u took the old one out once u get a little in there hold it tightly and slowly pull on the remaining strip little by little u will see it go in almost by it self as u pull the cushion out to get it in the Grove were the old one came out from hope this helps