Awesome! Congrats! It's so great to find G1s, especially when you get to dig and possibly find more. It's kinda thrilling!
However, in the future, you don't want to submerge your ponies in water, unless you plan to open them up to let them dry out completely (I know you opened Sea Breeze but I'm not sure if you were planning to open the rest, so I thought I'd mention it).
Anyway, I'm really sorry to hear about poor Sea Breeze. Some G1s are just REALLY tough to crack open! I had a Tunefull that I ended up ripping a tiny bit, too, trying to get her head off (she needed a tail - I HAD to get in there!) So I know that pain. And then I had a Wig Wam whose head wouldn't budge at all. I was so frustrated that I almost wouldn't have minded tearing the plastic a little, if only I could clean out his rust lol. I never did get it and ended up trading him. =P The good thing is, there are ways to hide issues like that if you can't fix them. Display the pony a different way, use their hair to cover it, add an accessory to hide it...etc. But good luck if you do decide to try fixing it!
Also if you do rehair her, please don't throw her tail away! There is probably a tailless Sea Breeze out there who can use it! =)