Robert, I cashed in that 69 spoiler (which probably was perfect for a 1969) last year and found a perfect one for our 1968s. Fits perfect and looks correct. Big difference in the workmanship.
Do a search of my spoiler posts over the past year and you will find the details.
'68 428 HO M3 Monster, 4-on-the-floor! Need I say more?