Hey fasteddy, welcome to classicbroncos!
Yep, time for some tweaking of parts to work with yours.
For the backup lamp switch, the originals from later '66 to '77 with manual transmissions a small plunger-type switch was literally clamped to the lower steering column so that when the column shifter was in REVERSE it pushed the switch. Simple.
In your case, a floor shift was never offered by Ford, so you will have to come up with something using either aftermarket parts from Hurst or whoever, or source a standard plunger switch as used on Fords and GM vehicles (and probably most others) and rig up a bracket.
Actually, the original Bronco version was very compact (
https://www.wildhorses4x4.com/product/3-Speed-Backup-Light-Switch/Bronco_Performance_Lights) and might be easier to make fit in the limited space offered in Broncos. Some floor shifters even have a place to mount a switch so that you don't even have to make a bracket like I did.
You'll need to do something similar for the brake light switch. Since the '66 pedal does not have the pin sticking out to mount the standard Bronco light switch to (
https://www.wildhorses4x4.com/product/Brake_light_switch/bronco-brake-pedal) you will need to fab up some kind of mounting bracket to hold the standard long-throw plunger switch.
You can decide whether a compress-to-activate or an extend-to-activate switch would work better for you. There are a few discussions about how others did theirs, but I don't have any handy links saved. Sorry 'bout that.
Luckily there was one fairly recently so someone should be able to direct you to the discussions.
Good luck.
Paul