The reversed 4th./5th. shift position is only on the "RTO" series transmissions, with 10th. gear overdrive. It's possible to change from direct drive high gear to overdrive by simply assembling the cluster gear differently. I've converted direct-drive transmissions to OD by swapping 2 gears on assembly.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!