there are two types of paddles dependant on drum fitted
count the number of holes!!
now yes they just slot in, but thats subject to wheter the locating tab is still attatched to the drum!!
if u look where the paddle fits , about half way down the drum , there should be a small piece of metal stuck up, if its still there all is good
the paddle slots in and pushes backwards, the metal locating tab then flexes and repositions itself behind the paddle to stop it coming out again
if its broken, then it aint pretty, trust me
hth