I have an early F14 with the clear back board flashers but my wiring has different colors than yours, but doesn't match the manual either.

I have re-wired mine with the extra red flashers and think I can piece your wiring together for you.

You mention that your PF is dimpled but no screw installed however, this isn't totally true. You have wiring and it looks like a socket was screwed in on the left side. The service bulletin that went out would have the wiring and socket removed from that side entirely. The way the later machines went out was only the clear and blue flasher and no flashers on solenoid 7. So here is my assumption on how you should wire this baby up:

1) Left Red Flasher - Orange pair to socket, White w/purple to bulb dimple.
2) Right Red Flasher - Orange pair to socket, White w/purple pair to dimple.
These 2 flashers should flash together and be on Flasher (solenoid) 7

3) Yellow wire gets soldered to the same lug as the 2 red wires on the blue flasher. (alternatively you could try the yellow wire on the Orange wires of the red socket)
4) Clear Flasher - Other end of Yellow wire to socket, white wire to dimple.

You have 2 sets of flasher power in your area, orange and red. On mine, I only have Red flasher power and all 4 flash bulbs are powered by the same red wire. Not sure why you have Red and Orange but I'm not sure it makes all that much difference anyway.

Can you tell me what color wire is soldered to A7 on the right side of the diode board under the playfield?

its mine...

meeting pat 2013 novembre 057.JPG

I also have early version (clear flash/clear dome/44 sockets under arrows) and I also wired the extra flashers in. I just reversed the service bulletin that disabled the flashers
http://mirror2.ipdb.org/files/804/Williams_1987_F_14_Tomcat_Service_Bulletin_41.pdf

When reversing the mod the red pair and yellow wires stay on the blue flasher, remaining untouched basically.
The orange pairs should be found tucked away, taped somewhere near where the original flashers were mounted. One pair provides flasher power for RED1, the other to CLEAR. What you should end up with is this:

before.jpg

There is also a handy youtube video on the subject:

When I reversed the service bulletin to wire up the red flashers, there were no wires tucked away and it was obvious that the red flashers were never installed (dimpled holes never had screws in them). Also, there wasn't a wire on A7 on the diode board.

Looks like pinballfan's machine is wired just like I told the OP to wire his up!

I didn't go over it thoroughly, but when I skimmed it it looked to be correct. It's been a while since I did mine, the orange are just going to originate from multiplexed solenoid power somewhere and you are correct that it probably doesn't matter, on mine they were just taped and tied up the the harness near the flasher area. I don't even think they are on the game schematics.

I generated a schematic for all PF flashers including the diode board and Proto flashers. I will post soon.