It may sound funny, but on a RHD car, the Mechanism is much simpler than on a LHD car.
On RHD cars, the Clutch Pedal is right next to the Transmission & is attached to a bracket that is attached to the cross shaft which protrudes slightly from the Transmission. There are no other Linkages etc required.
On the LHD cars, the Clutch Pedal is as far removed from the Transmission as it can possibly get, & that means that the Mechanism to link the Clutch Pedal to the Transmission means that a Rod has to travel inside the Brake Pedal Assembly all the way from the Clutch Pedal to the Transmission cross shaft.
On RHD cars, both the Brake & Clutch Pedals mount on the same solid shaft.
Also, on RHD cars, the Accelerator Pedal is very protected, as it is located right next to the Cowl, while on LHD cars, it is sitting out in the middle, where an irresponsible passenger could press down on it.
The only problem with RHD cars is that as these model Fords were originally designed for LHD, the Starter Motor is located on the Right Hand Side.
When the Steering Box is on the Right, if a Starter Motor has to be removed, it is not an easy task, as the Steering Column has to be lowered inside the car, plus the Engine has to be jacked up on the right hand side.
However, with the longer wheelbase Mercury, removing the Starter Motor is no problem.