Hey guys i hope some one can help me.

I have a 2006 BF Egas sedan sitting on stock springs and shocks.
Last weekend i was able to get my hands on a set of Monroe gt struts with king KFFL-57sl springs but i need to know what springs to put in the rear to make it sit level.
Will the Gas tank make the rear sag if i get sl springs and can i use the standard shocks in the rear untill i buy some bettter ones?
Also if anyone could direct me to a picture or 2 of an Egas sedan that has been lowerd this way that would be great too.