You could do this, 4.3 GM with an auto trans then mount your Toy tcase through an adaptor just like some do on Toys. That would eliminate the need for it to be divorced and then you wouldn't need the intermediate shaft.
i would do this, in fact, some th350/400 older 2 or 3 spd autos, are very short, so they wont take up that much space- i bought aaron his 92 blazer with a 4.3/700r4/np23? for 280 dollars-it cost me another 500 to get it registered so i could drive it to him-but you probably wouldnt need to do that
keep lookin, sweet stuff will pop up sooner or later