I recently changed my tranny fluid on my N/A (W58) to Redline MT90, good stuff just like everyone says
The TSRM says 2.5 us. quarts, I used one of those 2 tubed oil transfer pumps to fill it up the TSRM way, not through the shifter, it took about 2.8 qts I'd say, when I took out the tube, there was a steady (but thin) stream, which I let drain for a minute until it was just dripping. It didn't seem like a third of the bottle drained back out, but I'm guessing It's alright and I'm good to go!
The car has been driving & shifting just fine!