1990 270DA common leaks

Hello everyone, I am a proud of owner of a small fleet of Sea Rays so I know my way around one however I just bought a 1990 270DA to replace my 83 245 Sundancer. The 245 is a great boat but needed to go bigger due to growing family. I am new to this style and I noticed upholstery is definitely a common problem on these which I intend on replacing most of. Now to the point, I have noticed several water stains in mostly the headliner in several areas and some of it is still wet (even after I shrink wrapped the boat). I intend on going on search and destroy for leaks in the spring. Just wondering if any of you can point out some common areas. The aft cabin is the worst I plan on redoing the entire thing but want to stop the leaks first. I suspect A. possibly the radar arch is leaking where it mounts, B. the canvas seemed to be letting alot of water in around the arch (poor design) and possibly some of it might simply be coming in through the dash/instrument panel? Up front I am suspecting some rub rail leakage as well. Just want some thoughts from similar owners who have dealt with this. Any advice is greatly appreciated thanks!

I had a '92 290...same boat. Get about a foot of suitable tubing and secure it to the business end of a tube of marine grade sealant. This will allow you to properly caulk the "arch to hull" joint.

Excellent thanks. Starboard side definitely looks like it could use it but yeah like you stated little hard to get a conventional caulk tube in there. Thanks for the input that's definitely one of my suspicious areas.