I think I want to go for the 6.5" screen or 7" screen. Something bigger than a 3.5". I read somewhere that the '01 sports dont have a full double din opening and that its something like 1.8. Do they have any kits out there that I can use to expand that opening to make a double-din fit?
Scosche does--or at least did--make a double-din install kit for 1995-2001 Explorers (2001-2005 Sport Tracs, 2001-2003 Sports).
See Scosche's catalog:
http://scoscheweb1.scosche.com/pdf/Scosche_2007_001_090_kits.pdf
Look at page 19 and product FD1330B and note the double din icon after the product photograph. Also look at page 22--same product.
Also see Scosche's web site for this install kit:
http://www.scosche.com/scosche_caraudio.aspx?ItemID=FD1330B&CategoryID=5.
This kit will allow you to install a 7" double-din unit.
For a place to buy it (never used this retailer, though, and their reviews are less than stellar):
http://www.sjgreatdeals.com/sisfd1330b.html. Amazon.com also has them through third-party sellers, and Amazon offers buyer protection.
You will have to trim a little bit, but nothing terrible. The kit has a filler piece and should cover any openings.
I took a chance and placed an order for two from SJGreatDeals. I figure that if they screw up a $20 order, and in the worst case scenario, I am out $20, it is not the end of the world. If I get them, I use one to install a Pioneer AVIC-Z2 and sell the other to a member in need.
Good luck with whatever you decide.