i found a way of fitting the barbed ends in black hosing and figured that it will be the same for a splitter and my way is easy 
 
heat gun (600 odd degreees that i stole off my dad) (Y) heat up fitting for a couple of miniutes  
 
push real hard on the hose  
 
abra cadabra fitted (Y) and in under 10 mins  
 
DAN  
 
would this work for a splitter if it worked on fittings?