At 42 1/2" you will have to limit the draw length to less than 21" and even then the bow should bend throughout it entire length. You could splice the two staves together at the handle and make one full sized bow.
You could sinew back it to get a little bit more drawlength, or assurance I should say. I would shoot for a backed bend in the handle d bow if it was me. Or you could splice some siyahs/recurves/molly levers on it too. Although, one of my first "real" bows I ever made was a 36" (or so) sinew backed osage bow, made from an osage branch a guy in kentucky let me have after he cut down an osage tree in his back yard. It might of been longer as it seems unlikely to me too, but that is what I remember, and it was a small bow. I made the bow with a kitchen knife and some sandpaper I think, I might of had a couple files too. It was the first sinew backing, and the first hideglue I had ever made as well. I had just discovered TBB's and was on a roll,
. The bow pulled about 50# or maybe a little more at my full 26" draw. (Stacked like crazy.) And only one limb had about 1/2" set. It didn't have the best tiller, after sinewing backing, the tiller went a bit asymmetrical. It was also the first bow I ever gave a nice finish too.
