This part at the bottom, @ $329 is probably all you want to spend on that 318 Dart.
It will run like hell, and all you need is the 7/16" bolt hole Flex plate and ARP bolts.
The above, plate requires a "new" Dakota size small starter to clear the edge of the plate on a 904 trans. The one below does not and fits the old Mopar starter.
http://www.ebay.com/itm/ACC-53023-7...ion-/390938097121?vxp=mtr&hash=item5b05b9f5e1