All the numbers match up to a 2003 SX 195 BR GLASTRON.
Engine serial number: 0M378066 Model number 4211025PS 1998M MERCRUISER 4.3L ALPHA 2 PC 4.3L ALPHA
DRV: 0M450642 5121400LS MERCRUISER ALPHA 1.81:1
TRN: 0M552890 6111001LS MERCRUISER ALPHA TRANSOM
Engine manufacture Date:
09/13/2002
This is an unusual situation to where it makes it hard to find your service manual.
With your situation in trying to find the correct service manual for your engine with your engine serial number I'm going to recommend that you call Mercruiser directly at
405-743-6566 and ask them to look up what service manual you need for your engine.
http://www.mercurymarine.com/utility/contact/index.php
I know I can take a guess at what manual is correct for your engine, But to be honest it would only be a guess.
The manual number that comes up for your engine serial number number (32) is incorrect because that covers EFI and your engine has a carburetor(correct)???
My belief is, it will be number 25, But you should call for a second opinion.
If you do call, Could you let us know what they tell you? Thanks, And good luck with it.