Dual exhaust on a single exhaust car

hi my 73 Dart had a very badly made dual exhaust on it so I purchased the summit dual kit but since it’s a factory single exhaust car (I think) the summit kit wants me to drill a hole in the floor to make a hangar. The car has a spot before the axle for a muffler hangar to attach too. But the passenger side exhaust barely clears the driveshaft. So all in all I’m just wondering if there’s a company that makes a better fitting exhaust long tubes back honestly turn downs are preferred. Thanks for any insight.
Barely clears WHEN?
on the ground at ride height?
or with the wheels hanging down on a 2-post hoist?