Exactly!! why wouldn't it work, obviously the "someone" doesn't know his shit coz it seems to be working fine to me. As long as the are both 4 tooth split, you shouldn't really have any issues. Only thing is, looking at the last pic, I would of tried to shim the clutch bell forward 2mm so that the mesh is in line.
Apart from that -- good job and nice vid!
Oh yeah -- loctite is a must for the eng. screws!!
BTW, it doesn't matter how much of a Frankenstein it is, you just do whatever ya gotta do to get the thing goin
(I've got a few frankenstein's myself -- but they all run!!!)