That boat is 100% worth fixing as it looks pristine. The tubes themselves are thermo bonded and don't fail. The glued on parts will just start falling off the boat due to glue age. I like Stabond for glue which is available from the USA at NRS. It will take 2 possibly 3 quarts. The entire floor needs to come off and be reglued along with the transom. It is a pretty big job and will take between 20 to 30 hours. The little bits around the boat may also need gluing like the front D-rings, and the front handle. I say that since they are often used for anchoring. An anchor bridle run thru the front with fairly large knots gives 3 avenues of failure before being set adrift.
Was the engine supported by more than the transom? If not try to use a block setup and with the outboard down, get the blocking so you have to lift the outboard a little to slid the last block in, or use the trailer jack to lighten the load on the transom, but more importantly the twisting load trying to rip the transom off the boat. Goes with slackening all the tie downs when stored, or things tend to fall off.
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