What year spindles do I have?

[smh292]

I bought a lowering kit from a guy on ebay. He said the kit came off a 71 C10. The kit consists of drop spindles, front and rear coils, rear 1.5" lowering blocks and new outer tie rods. I tried installing the spindles a few weeks back and I tried using the stock tie rod that was already on the truck and there was a lot of slop in the hole on the spindle. In addition, I think the upper ball joint is too long and the castle nut on the axle was a different size than stock. I did some research on here and some sites and it looks like CCP using the 73-87 spindles in their kit. I have a feeling that these spindles are for the newer trucks. Does anyone have some measurements I could check or know a way I can ID the spindles yr? Does anyone know what all would need to be swapped out to make the spindles work?