Some 73-87 suspension questions

[AndyBare]

Hey guys,
Doing a front disc conversion on a 67' dually, but I've got a few questions about the 73-87 suspension parts.

• Can C20 (upper/lower control arms, spindles, springs) be easily swapped to a c30 truck? Are the bolt patterns on the control arms the same?
• Would C20 parts be strong enough for the C30 body, even if the truck isn't going to be used for a ton of hauling?
• Are C30 stock-height spindles sold online? If not, can I use a lift kit to counter a C30 drop spindle?

That's about it for now I think. With the answers to those questions, I can get moving, but as this is my first brake conversion, and I want to be as knowledgeable as possible before purchasing parts and then asking more questions(haha).
Thanks!
Andy