Lift spring question.

[1979C20]

My friend thad has a 79 k10 and he has a 6 inch lift with 35's and the only rub on his inner rear wheel well because of his wheel backspacing. Hes using stock brake lines in their stock positions too, but theyre tight. So, 56" stock rear springs used on the front will give 3-4"s of lift after sagging. So, 6" lift rear 56" springs on the front will equal about 10"s after sagging? And then 6" springs anf 3-4" blocks will level it, maybe?

[1979C20]

Does anyone know how far forward i need to move the front spring hanger? And i have to move the spring perches on the axle too, right because i have to move the spring hangers to the frame?

[Irish_Alley]

you would have to keep the axle center so you would have to move them both front and rear and then you would have to see what the difference it might now be as easy and re-drilling holes since the hole might be close to the old holes then you have to worry about how far forward the front goes it might be weaker idk i would measure a 6" lift front spring that has been used and compare it to the rear spring that has been used then split that up and see where everything sits