Looking at the same question for my 1968 Firebird. Not sure which way to go. I have an 8 Quart pan that hangs below the cross member as well. 2" may be to much. I figure 1" could be handled with springs without messing with geometry to much. That way I could go to a stiffer spring as well to keep the pan off the pavement.
Post which way you go and your results please.
Montea is exactly right... Yes, springs will do the job but you will lose some suspension travel and harshness is a common by-product of a spring only drop.
If you can afford the spindles go with them. You will get your drop with no loss of suspension travel or ride. Either way have the front end re-aligned after you get it back together.