well, like i said in the 1st post.
it looks like the ears on the stock case, are longer, or the holes for the mount are further out. cuz when i line up the mounts on each motor its more outward on the stock motor and really tight on the new motor. so, when i tighen the bolts down, it already puts stress on the mounting ears.
my LHS says i have to use these mounts, because i have to adjust the front to back engine placement of the clutch bell on the spur.. but solid mounts would be much stronger, and could hopefully be thinner also.
look at those motor pics.