First, I do not own a grapple, but there have been several comments indicating that the FEL lifting capacities are computed to include a bucket, presume the OEM bucket.? The rating may note the capacity a specific distance forward of the hinge pin but that reference could be applicable to other implements, such as forks.
I note this because my owners manual does not mention that the bucket weight is calculated in the capacity. I purchased the MX w/o an FEL. When I purchased the new FEL from a Kubota dealer in 2017, they readily deleted the bucket from the purchase. Got the impression that bucket & SSQA were a la carte in the purchase. If the bucket is included in calculation, should Kubota specify the OEM model or a bucket weight allowance
BTW, lifting capacity on my MX very limited. 1000 lbs lifts rear w/ an implement 3 point attached. Tires not loaded due to increased turf damage during wet spring mowing Does have 900 lb. All glass aftermarket Agrital cab.