If your still using the 49 leaf springs, they will probably flatten out a bunch when you get the load on it. Expect the leafs to be nearly flat once loaded. Pile some weight into the trunk to equal what the gas, seats, and everything else missing will add up to, bounce the rear end up & down a few times, then measure the distance between the top of the axle and the bottom of the frame. You should have about 3" to 4" clearance.
Also, while its loaded, check your driveshaft clearance and u joint angles.
If your u-bolts are hanging below the rim surface, you need to cut off the excess, you only need a 1/4" to a 1/2" below the nuts of the u-bolts left after torqueing. Cut them after you are finished doing anything with the u-bolts because sometimes after cutting, they are a bear to remove and reinstall the nuts, if you would need to.
That car pictured on the link to the HAMB would be a pita to drive on the roads around here. Your 3" lowering blocks would be bad enough. Gene
