OK ,so there are no 1000 reverse switch Gurus out there!

I have a B10 wreck and a FS5W60A and FS5W60L (dogleg) 5 speeds and set about fitting them to see what mods were required and which was the easiest fit.

The 2 boxes both fit, just!
With the standard pattern 60 series box, the reverse switch totally clashes with the factory right tranny mount. So there are 2 choices---plug the reverese switch and fit a manual switch in the cabin or carve the original mount off and keep the switch. Even then, the rev switch wires have about zero clearance so cutting a 35mm hole in the tunnel and covering with a rubber gromett would be wise.

The dogleg box reverse switch is about 50mm higher than the standard pattern box.
This means you could get away with NOT carving the original mount off but the switch wants to protrude about 15mm into the tunnel. You have no choice but to cut a hole in the tunnel if you want to keep the switch.

With either box a custom tranny mount is required
Conclusion: to keep it legal, I will use the standard pattern box and carve off the original mounts.
But before I cut a hole in the tunnel of a decent car, I am going to see if I can find a reverse switch which is shorter than the original unit.