Alter length of secondary beam over rest

[Andrew Bernard]

In the following MWE, I want to have the secondary beam on the last note B much shorter, so that only the main beam goes over the rest. How can one achieve this? It would be good if that part of secondary beam was the same length as the other tertiary beams.

Andrew

%======

\version "2.19.83"

{
  \stemUp
  c''32[ c'''16
  \set stemLeftBeamCount = #3
  \set stemRightBeamCount = #1
  e''32
  r16 b''16]
}

%======