what spring perches to use?

I'm doing a T.
I have a new frame that has a sucide perch set up for a 1 3/4 wide spring now.I have a 40 ford solid axle and wish bones.Where do I go to get perches and shackles that will allow use of a 1 3/4 spring and are long enough to go through wish bone ends?All the ads for perches that I've seen don't give measurements.Whos a proven source for what I need?

 

Most of the new perches, Speedway, SoCal, etc are made longer than stock to accomodate lower shock mounts. They should work just fine. The best price will probably come from speedway. Good luck