Anything I say about this topic has to be based on highly unreliable memory; I don't want to think how many years have passed since I had that old kit in front of me. But I did build it several times and I think I can remember it fairly clearly.
The big problem with those pinrails is that they aren't to scale. The pins are too long, and the sections of the pinrails abreast the masts (where the lower deadeyes are mounted) are too wide. I don't remember how much too broad they are, but I strongly suspect the deck couldn't be dropped between them.
In reality, the pinrails do get a bit wider abreast the masts; they have to, in order to provide space for the deadeyes. But, unless my memory's playing me false (certainly a distinct possibility), Revell exaggerated the distinction between the wide and narrow portions.
The bottom line is that if the pinrail projects further inboard than the waterway (which is molded integrally with the hull halves), the deck components will get hung up on the pinrails. But the only way to find out for sure would be to dry-fit the pieces and give them a try.
Youth, talent, hard work, and enthusiasm are no match for old age and treachery.