Ya , finding a working trim for a 33 year old motor will be a bit of a long shot.
As TD said the CMC unit bolts right on, works right out of the box, comes with a warranty and will work for years, I have had one for 5-6 years now with out a single problem, money well spent.
OMC made major changes to their T&T system starting in '78. They continued with that design for many years. Post '78 you can pretty easily find a complete working system on eBay. Pre-'78 you are pretty well screwed. They come up rarely and when they do they go for close to $400. And this is for old used units. The CMC is pretty much the only way to go. I have a '73 that I'd love to add T&T to so I feel your pain.
