Adding the old firm to English premier league

Sorry if this has been asked before but I couldn't find it.
I wanted to try adding both celtic and rangers to the English premier league. I am very inexperienced in using the editor however I thought it was just a matter of swapping with a team already in the EPL. I tried it with celtic and everything went fine until after my 3rd season I finished 2nd in the league and was looking forward to plying my trade in the champions league, and am not even considered for a champions league place. Is there something obvious I haven't done or is there something  I can download with both celtic and rangers in the EPL without these problems.