Who knows shackle dimensions? Or has a C1500?

[pvfjr]

I'm needing a longer shackle for the S10 project, so I'm looking into lowering shackles. The best price I can find is on a 2" lowering shackle for a 88-05 c1500. I don't know what springs and bolts these use, and would like to find out exactly what it is before I buy it. The S10 is getting 2.5" width springs up front with 9/16" bolts. If a c1500 has 2.5" springs in the back with 9/16 bolts, then we're good to go. Anyone know?

Here's what I'm looking at.

 

[pvfjr]

Anyone? This needs remedied soon...

Drooped

Compressed - front just barely came off the jackstand.

 

[pvfjr]

Come on guys, auction ends today, I wanna get in on it if it'll work.

Does anyone at least have some unfounded conjecture? They used 2.5" springs for decades before that with 9/16 bolts. Did they continue after 88? Or did it change?