Static lowering limit

[BuffettTruck]

After my TB died, I got an 05 Tahoe Z71 Wannabe (2wd version). I am looking at doing a 2" front/ 3" rear lowering on it. I think after I put some 20"s with 60 series tires on it, I should have the sporty, aggressive look I want without sacrificing too much in comfort.
My question is, if anyone knows: If I decided to go lower in the rear, how low can I go before the frame needs to be modified to allow full travel? I ask because I don't want to have to go that route. Not yet at least.

Thanks.

 

[Blckshdw]

Would it be as simple as measuring the distance from the axle to the frame after you get your drop kit installed?

Edit: And maybe load a bunch of heavy stuff that you'd normally put in the cargo area.

 

[BuffettTruck]

Sort of. And I suppose this is where some generality is involved. It depends on the spring load of the lowering springs too. When I used to use blocks it was that easy. Just remove enough bump stop to account for the block, because the leaf springs didn't change. Lowering with coil springs is something I am both familiar with and yet don't have personal experience. So I don't really know if the lowering springs will result in more compression when I hit a bump or not. 3" lowering springs could result in more or less travel. I am hoping someone has experience with coil springs can chime in.