Check This MR Trans Out, Never seen one like this before...

[Hans@GZP]

MB811031 is the 18 spline and MB111883 is now all versions of the 25 spline 5 speed.

[Hans@GZP]

oops, never mind... looks like they added an addendum to the part number for the 18 spline. No more 18 spline from the dealer if I read it right?

[GTOJOE]

that looks right but mine is in Japanese so I can't tell 100%. But looks like you can't get the 18 anymore.

[aaronatstate]

I've seen a few like that. I haven't seen any counter weights on 5 speeds that go straight out. Most of them face down on a 90 degree angle.

Ive never seen it I have 3 5speeds in my garage right now. Maybe its a JDM thing?

[MR2]

I've never seen that counterweight design before either wtf...what a PITA..would hit the Lower radiator pipe surely..

[Hans@GZP]

[GTOJOE]

i'll raise you...

[ZeroAU]

I'm not aware of any difference between USDM & JDM 5 speed gearing though. Did Mitsu even make a 1st gen GTO MR?

Dont think so, there was 500 MR's made on the Z15 platform between 1994 and 1998 as best as I know.
USDM final drive was 3.872 and JDM is 4.154 on the 6 speeds, all the actual ratios on the individual gears should be exactly the same.

[GTOJOE]

There is such a thing as a 5 speed MR. there just isn't such a thing as 5 speed MR gearing. Also the 5 speed MR was a Z16A not a Z15A.

[ZeroAU]

That would probably make them some of the last of the 1993's then before they switched over in 1994 with a bit of an overhaul to most things.