You're going to need the 8cars per trainer; I googled it and got this site first, which has a link for the file:
http://www.geocities.com/jmanderson_200 ... ainers.htm
I believe that the "zero clearances" feature is what you'll want to so you can place track that intersects itself. Hope this helps.
EDIT: Just to check myself, I opened it up, and the option you want will be under "Edit Ride Stats" (shortcut: F10), then you just need to select the coaster you want, toggle "zero clearance", and hit apply.