Quote below is from IMCO installation manual.

9. SCX Drive is 19 7/8” from crankshaft center line to prop shaft center line (2” shorter than standard Bravo). SCX4 Drive is 17 7/8” from crankshaft center line to propshaft center line (4” shorter than standard Bravo).

I am 100% sure you are WRONG.

SCX upper is 2" shorter.

https://cimg3.ibsrv.net/gimg/www.off...eb305a9c0c.jpg
This is my set up.
IMCO SCX upper standard SC lower with standard vertical shaft. Propshaft is 2" higher than standard Mercury XR.
If you want a real answer to your question and not a bunch of guesses, call Fred at IMCO.

SCX-4 upper is same dimensions as scx except for the cavitation plate that is bent up (lower to upper bolt pattern also different) to allow for the -4 lower prop clearance. The lowers are the difference between them. But yes a scx with a scx lower or a scx with a -2 sportmaster or -2 sc lower make the same x-dimension as a bravo with a -2 lower.

Those are -2 lowers pictured, not standard lowers

correction: Those are standard lowers, angle of cav plate tricked me. So your setup is the same X-dim as a standard bravo setup.

I was just talking to jeff Harris to confirm. He said the scx4 is -2 in the upper -2 in the lower. Regular scx upper and lower is -0 in the upper -2 in the lower.

But in any case silvergts is wrong lol

Don’t want to beat a dead horse here but the scx-4 upper is the same dimensions as the scx (obviously the splash plate is different). Otherwise it would not fit in the gimbal ring. The scx-4 lower is 2” shorter than a scx lower, which is 2” shorter than a standard bravo/sc lower

https://cimg0.ibsrv.net/gimg/www.off...cd67ed7d46.png
https://cimg1.ibsrv.net/gimg/www.off...77597d9a59.png

I did the conversion last year and checked with imco 2 times.
The SCX upper is the same height.