Tuchase,
Good eye! Yes, parts 1 and 2 are the main hull pieces. I recently bought an old (1960's) version of the Constitution for spare parts. It cost $9.00 on ebay. The kit is complete with the exception of the hull halves. So, given the comments on this thread, I contacted Revell of America via email to see if there would be any difficulty in replacing the parts.
I was completely above-board with them. I explained the situation fully, except for any mention of this thread. I also informed them that I could not assert that the pieces were missing as a result of any problem with Revell. In fact, I offered to pay for the parts.
They responded by informing me that , although their parts replacement policy only allowed parts to be replaced in recently purchased kits from dealers, they would be happy to replace these pieces for me. They also informed me that the parts had already been shipped. I will let everyone know when I receive them.
Bill Morrison