Is it that much heavier than a regular table or a corn headIJ Seems like it would handle it no sweat, I know of one guy who had a A438 head on a long tail K2, it had a support kit for the drive axle but it did it.
I don't use the AHHC on my combine, always lifting to clear stones. I suppose if I wanted to use it, I could put an old-style feeler-bar assembly under the header and use the mechanical linkages on the K2IJ
A local guy just bought a long tail K2 diesel this spring, his neighbor, a former F owner argued with him about the K2 being able to run an A 430 because that's what he had on his F and said the K2 would never do it, I chuckled because I remembered Russ' pics of his K2 with that 4-38. Wish I could neighbor to sell me that K2 diesel, that is a sweet machine.