Denis wants me to clarify that when the outwales are mahogany on a Morris, the top cap is too... but the inwale in spruce on closed-gunwale Morris canoes, even if the rest of the canoe is mahogany-trimmed.
It appears Bert Morris was very fond of mahogany, so the spruce-parts were stained to match the decks, etc. Our Veazie (Morris second-grade, factory-direct model) has maple trim that is stained mahogany.
Your canoe-- #8392-- is much like the needier-canoe in the video-- #8435. It would be interesting to know how many canoes Morris turned out in a week--- our canoes may have sat side-by-side at one time!
Denis has a stain-formula that works well for matching the Morris mahogany stain on interiors and rails and such. Without stain, the spruce would be lighter. Some Morris canoes appear not to have been stained at the factory (i.e. they have a light interior). I'll look through my pictures because I can't remember if the light-interior Morrises have light rails as well. Your canoe appears to have the more-common dark interior, so the rails were probably stained.
This is the stain recipe Denis used on our Belle Isle Morris (or Morris Molitor):
Using Minwax products, by unit (meaning eye-dropper-full, teaspoon, cup, truckload, what-have-you):
2 parts Red Mahogany #225
2 parts Golden Oak #210B
1 part Special Walnut #224
1 part Sedona Red #222
Some folks prefer the unstained appearance of the wood, even if it was originally stained. Remember, this is your canoe and you can finish it the way you choose. It seems to me that the lighter-interior Morris canoes may have been a "buyer's choice", because the lighter boats appear here and there, willy-nilly, throughout the database and so don't indicate to me that there was a decision from Bert on High to discontinue staining. So-- as with exterior color, interior staining is "owner's choice".
I went though a bunch of pictures and will attach examples of Morris canoes with or without stained rails. As you can see, contrast looks nice too-- whether it's original or not.
Also will add the picture of our 17' Veazie-- The Family Canoe-- a picture taken at Assembly 2008 by Ted Michel. It's Charlie with me in the bow, Bertie hanging over the rails and Denis in the stern.
Kathy