I sold my GX355 and picked up a 75 hour X720. I found a 45 loader locally and will pick it up tomorrow. Tonight I ordered the pressure relief valve and the free wheeling lever made to clear the taller valve. My question is this- I ordered the BW15043 2WD valve for $167 instead of the AM121248 2WD valve for $285. I don't understand the difference. Online I have seen the two part numbers used interchangeably so I bought the cheaper one. Did I screw up? Thanks for any help. Bill