Thanks, MN3
Badfish:
I think you're right: the salt is the main responsible of the difficulties. if you add some sand and dried grease... we have a strong bond between the pieces
I'll take some pictures tomorrow and send them to you.
I forgot to mention that when I saw how difficult it was, I removed the pop rivets to disassemble the front beam (and the dolphin striker. Funny name, in France we call it "martingale", used also for horses, clothes and games). I also disassembled the rear beam as well. I thought it would help if every hull was indépendant...
I didn't know PB Blaster. You know, I seriousely think you have in US more products (correct ?) than we have here in France. I neither known JBWeld, here we use mainly Araldite (epoxy resin).
I'll try to find PB Blaster here (Amazon ?) or something equivalent, I'll go to the car workshop.
Anyway, before coming on this forum, I read about lubricants. I tried to do something by mixing diluant and WD40, hoping It would penetrate.
About what you said about boiling water: I tried, but perhaps not enough... I'll try again tomorrow.
When I heatened with a "thermal cleaner" (not sure of the translation), I didn't heatened that much, because I dont want to damage the castaings.
What do you thing about it ? can I heaten much more ?
Anyway, thank you very much for your ideas and humour