The fix when installing the earlier small block V8 engines was to use a driver's side exhaust manifold for a 55-57 265 engine with the outlet flange at the front. I doubt if that would be an option with an LS engine, unless the exhaust port size and spacing is the same as the 265.

Edit: Check these out- - - -block hugger cast manifolds with rear outlets:

https://www.summitracing.com/parts/sum-g9080

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!