timer base cleaning help

[basspirate]

here's my dilemma: i have a1978 140 rude. i'm not acheving wot. the engine will get up to about 3300 rpms and wont go higher. the butterflies in the carbs are opening all the way. someone had suggested checking the timing base and it does move but after a certain point it sticks a little bit. can i clean it without removing the flywheel, just by spraying some carb cleaner up there or do i have to remove the flywheel. if i remove the flywheel should it be lined up to the timing mark or does the position not matter? also any other suggestions as to why i might not be acheving wot? i was told it's definatly not the prop size.