You'll need to have a rubber mount at the talishaft housing if you decide to add the X-member, so that will provide enough flexibility. It's really unnecessary, though, and it adds a degree of difficulty to changing a clutch, and/or any sort of exhaust system work.
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!