I bought a B18b1 with a GSR transmission for my Eh2 but my plan was to rebuild the engine first with my boss so I know how to in future. But we've run into an issue with rod bearing sizing and I've got no idea what size rod bearings are correct.
Going from cylinder 1-4, the code stamped onto the crankshaft is b2, b1, b2, b2. Based on what I found before I thought it would be in terms of bearing color(G=Green Y=Yellow) G/Y, Y/Y, G/Y, G/Y but when I put those OEM bearings of that color on, and tightened the caps down to 23f/t lbs, I wasn't able to turn the crank since the bearings seemed to be the wrong size. The bearings that came of of the engine when I took it apart were four green and four yellow which has me more confused. If anyone can help me out, it would be greatly appreciated.

My Eh2

Top is cylinder 1 B2 B1 B2 B2

 

OK, I find a couple of errors in your explanation above.

First, the markings that you described on the crankshaft are not ALL for the rod bearing identification... only the LETTER is. The second digit for the chart in the FSM is a number, and it is found on the side of each corresponding connecting rod. The number is split in half at the joint where the rod and rod cap meet. So, if your list above assumes that the number 1 piston hole has a "B" on the crankshaft and the number "2" on the edge of the connecting rod, then you got it right. If both the letter and number came from the crankshaft counter-weights... then you got it wrong.

Second, you are looking at the wrong rod bearing chart. The B18B chart has no "Split" color bearings... the top and bottom shell colors would be the same. It doesn't mean that you couldn't use split bearings to get the oil clearances down to the tenth of what you desire instead of two tenths, but the chart doesn't have the split colors in it.

 

Also, make sure that you are installing the rod caps correctly with the bearing tang on the exhaust side of the engine... both the rod and the cap... and make sure that you haven't mixed up any rod caps with other rods. Connecting rods are unique and the caps cannot be mix and matched without re-sizing the rod. Remember that the rod bearing number is stamped on the edge of the connecting rod - half on the cap and half on the rod.