73 340 4 speed Reverse.
Lock out light on dash location needed.

From another thread, I used @4spdragtop 's measurements for mine, these are his pictures I just took them out of the quote so they wouldn't be collapsed. There are structures on the back side of the dash that also help with location. I believe they were all in the same place for A-bodies at least 67-76, although I don't think it was an option for all of those years

location for 1968 4 speed reverse light on dash

4spdragtop said

Heres pics and measurements. Been a while since I took it apart. I'm not 100% but mine is a vert so there is a "Top" switch/bezel mounted on dash also. But I'm pretty sure it's the hole to left of steering wheel for "Top" switch.
2nd pic shows location of "reverse" indicator.
Sorry for upside down tape measure lol.
Looks like 2 3/16" -2 1/4" from left edge of dash where ashtray fits in to center of hole.
Measuring from bottom of dash 3 3/16" to center of hole. See pics for measuring points.
Looks like a locating hole for pin also.
Hole is 3/4"

Click to expand...

2 3/16" -2 1/4" from left edge of dash where ashtray fits in to center of hole.
Measuring from bottom of dash 3 3/16" to center of hole. See pics for measuring points.
Looks like a locating hole for pin also.
Hole is 3/4"