OK...I'm not gonna label my answers like DINO, but here ya go:
I think it will could pass emissions, but as long as the mods stay mild.
Don't go waiting $$$ on 31 spline or anything like that for your combo, but DINO is right:make sure you go to a respectable shop for the gears
You will have problems with getting the speedo accurate with a 93 tranny due to the 8 tooth gear on your tranny, I'm having the same problems with my 92...the only gear they make to work with the 8-tooth self-destructs.
BBK Equal length shorties are mint, they look good and they fit perfect. No worries about wires or plugs
Go to the boneyard and get a crossmember...its easy enough to swap.
AND KEEP YOUR OLD LADY AWAY FROM THE CAR!!!
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1992 LX:V-1 S-Trim ,Edelbrock 6037 Heads,Cobra Intake,E-303,1.6 Rollers,65MM Holley TB, 75 MM Pro M Mass Air, 190 LPH FP,24 lb injectors,MSD 6A and BTM,BBK equal length shorties,offroad h-pipe,Mac Flowpath Mufflers,Pro 5.0, 3.73's,Motorsport "C" springs,welded subframe connectors,Ponies w/ 225/50 Nitto NT 450's on front,255/50 BFG Drags out back,93 Cobra Spoiler
Daily driver 89 Coupe:BBK shorties,offroad,flowturds with dumps,soon to be cyber green