i don't know where you got your info re mighty comp cranks using 114mm spindle but sugino themselves publish that it is meant for jis 110 mm as double/103 as single, just like their couple other road double cranks that have become commonly used for ss/fg.

i used a surly dingle cog on my bike in combo with a fsa gimondi crank with the chainring on the outside & 103 mm tange bb, chainline was close enough with 3/32 ring & 9-speed chain & it was trouble-free for the short time i had it on. took it off when i realized that i never switched between the 2 cogs. but i will use it again to have the additional ratio available if i go through with a several day tour i am contemplating.