I guess it is possible: help I'm too low

[Ezzz]

Hey guys, awesome forum, been lurking for a while but this is my first post.

Bought a 69 a couple days ago, and while I love the stance looks wise, something needs to change.

The headers scrape on just about everything, and I'd guess the rear has less than 1" of travel. I want to raise and soften it up a little bit. I've read a lot on lowering from stock height but not much on raising from a lowered ride height.

According to the previous owner, it's on spindles and lowering springs. It also has pretty tiny 245/45/17 tires, that I'd like to swap out for much bigger ones. As it sits, the front fenders are 25.5" from the ground and the rear is 26.25".

Will taller tires raise it enough? New springs? New spindles? Do I just have to guess which springs, or is there a way to find out how much a certain lowering spring will raise my truck?

Thanks