Replacing stock speakers in Nautique Super Sport?

I need to replace the stock speakers in my '97 Super Sport. First of all, I was wondering how do I remove the stock speakers behind the panels. I think the panels come off. . .but how? Does anyone know what size the speakers are. I think they are 5 1/4". If that's the case, I have been considering replacing the stock speakers with some Infinity Kappa 52.5i's or MB Quart Discus DKD 113's. Does anyone have any opinions on these speakers or any others that aren't really expensive? Thanks.

My 95 has 6.5" speakers behind the 5 inch holes, yours is probably the same. The factory speakers are probably Clarion dual cone marine units. They actually make decent low volume full range speakers as mine ended up in my work truck. I replaced mine with Infinity 652s.

Yeah, I ended up getting one of them out and it was a 6.5" speaker. How did you like the Infinity 652's? I was also looking at those. Are you running them off an amp? Are the 652's a big improvement over the stock speakers? Thanks a lot!