sub level 'Los Angeles and beyond' reverse loop, finicky grade up out of it.

adjusting the grade to allow least throttle/DPUs, fine tuning it to allow longer sets. around 12-15 is the limit for 2 Kato road engines right now, seems like it has the space (length) to adjust the slope to allow at least 20 freight cars with 2 locomotives but the loop length is around 15 anyway.