Today I was able to confirm the Skytec 149 NL is a suitable replacement for the fwd facing air intake on the IO360-M1B engine instead of the Skytec 149LS.

The only modification required are the two lower Bosses (B & C) on the NL starter needed to be trimmed per the installation instructions - step #9
The NL Skytec model although 1.2 lbs heavier has a shear-pin set-up and hence in the unlikely event of a kickback, it should prevent damage to the starter and ring gear.
Cheers,