Powersteering box rag joint issues

[63frankintruck]

Hey guys, I have a 63 c10 that I’ve converted to power steering and the power steering gearbox is stamped 7802644L. I ordered a rag joint for what I thought would be a 72 Monte Carlo thinking these are all the same gearboxes but the rag joint that came in doesn’t fit the splines on the gearbox. Can anyone tell me what type rag joint or what number rag joint I need? Thanks for your help in advance!