Hey guys I wanna remove my door trims to get access to the speakers. Can't see any obvious fasteners??? and didnt want to jab around witha flatblade screwdriver without working out where the screws are??

Do you guys reckon changing speakers will improve the sound quality - on a budget.
Or do you have to do something to help the head unit out? Don't need to win an auto salon just want a clearer louder sound - I like rock heavy metal. Cheers