Nice job! Answers several question I had.

I know there is more to the scoring for the top FORD roll over lanes but I haven't done a glass off test to verify. At some point after completing the rollovers (not positive how many times it takes) a "sweeping shot" is lit (the FORD lights "sweep" back and forth) and it scores incrementally each time you go back though the lights. I believe it increases in 500k steps up to 2,000,000 for the final pass ( I don't know for sure if it starts at 500k or 1mil )

Edit : this is based on a Pro model

I agree that it isn't possible, probably was meant to be stack Burnout. I don't think you can qualify Burnout until the 6th drop has been hit but after that you can hit the captive 3 times and once the second GEARS ball drains you can select a new mode AND Burnout will start(I think I remember that working ). I'm going to check it tonight along with the FORD rollovers for the sweeping shot.

I just confirmed that you can "qualify" Burnout MB (3 lights are lit) before or after MB during Drag Race but it will not light the scoop until you complete the MB portion of Drag Race. You can't collect without switching to the next race/mode so basically if it is lit you would stack it by default.

As far as the top FORD rollovers as per the PDF "Initial lighting of all four “Ford” inserts awards TECH upgrade and ___"
So I guess the "... and ___" part is the sweeping shot where the FORD rollovers lights flash sequentially and is a 4-shot progressive starting at 500k and finishing at 2 Million.

Tuna
I'm not sure if I missed this before or just wasn't looking at it. Regarding the letters, I'm not sure exactly what you were trying to say but on the pro you collect (or light solidly) the flashing MUSTANG letters with the scoop just like the prem/le. I'm not sure what causes the next letter to start flashing maybe it is related to the spinner (maybe that is what you meant?)

No worries you have done a great job with this

As far as I can tell the spinner has little or no effect on the Mustang letters. I know that at the completion of a race the next letter in the sequence (always done in order) will start to flash and is collected at the scoop. As I was testing I did have situations where another letter began flashing prior to the race ending and maybe the result of a toolbox award, I need to pull the glass and double check.

I had a first tonight and don't see it in the rules set. I will need to confirm the exact activation sequence but after an indeterminate (3rd or 4th??) number of completions of the top row of FORD inserts rollover I got a "roving" light (like a second/variation of the sweeping shot) that scored 20 mil(that may have been due to2x multiply). EDIT-THERE IS MORE TO THIS THAN I FIRST THOUGHT. There are at least two more variable target shots after the "sweeping shot". I still need to focus on these specifically but as far as I can tell the top FORD inserts have 2 "roving" shots that light after completion of each level of upgrade scoring. After UPGRADE scoring is two inserts as "wide roving" shot and after UPGRADE MB is just a single insert "roving" shot.

I will keep looking over the pro stuff and let you know if I see anything.

Did you intend to word the Upgrade multi-ball description this way:

"Activated by earning all upgrades again (2nd time) after UPGRADE multiball has been played"

I don't think "multiball" should be there as part of how you activate UPGRADE multi-ball maybe you meant "scoring"

Check my edit above, it looks like several variable shots are available for the FORD inserts based on completion of all the UPGRADES. ( I now believe it is a 10 mil shot and I just had 2x scoring going) I'd love to see what others can determine.
Every time I turn around I find deeper and deeper code elements

Here is the latest I found on the top lane FORD inserts and sweeping/roving (not random ) shots.

These shots are adjustable in the menu for the number of shots required to complete them:
"Sweeping" shot is begun after the first time the top FORD inserts are completed. the lit inserts sweep back and forth. Default is four shots to complete. Scoring starts at 500k and rises 500k with each shot finishes at 2 mil
"Wide roving" shot is begun after completing UPGRADE scoring AND completing the top FORD inserts twice. It is "wide" because two inserts are lit for scoring and move back and forth. Default is two shots to complete, Scoring is 2.5 mil and 5 mil.
"Roving" shot is begun after completing UPGRADE Multi-ball AND completing the top FORD inserts twice. One insert is lit for scoring. Default is one shot to complete, Scoring is 10 mil.
2x playfield scoring applies if active.
If anybody finds any discrepancies let me know