MX cruise-o-matic to C6 swap questions

[merc66rkm]

Hey folks. New member here. I recently installed a freshly rebuilt 410 FE and the original MX cruise-O-matic in my '66 Mercury Montclair. Long story short, something happened and now I need a new transmission! Instead of putting $ into the MX, I'm switching to C6. The total length of my MX is ~34" long and about 19.5" from bell to cross member mounting bolts. I have a line on a rebuilt C6 out of a '72 truck with short tail shaft and a fixed yoke. I know I need a longer output shaft and a longer tailshaft housing, but which ones? Seems like there are multiple length 2wd output shafts. I'm hoping I can avoid messing with driveline, because it is all brand new. Also, my speedo driven gear is 18 tooth, and from my research it seems like I need an 8 tooth output shaft to make it work. I will be putting in a wide ratio gear set in as well. Tips? Thanks in advance.

[mmerlinn]

I don't have any answers to your questions, but I do have a heads up for you.

All 66 Ford automatic transmissions, Cruisos, C6s, & C4s, all had a Green Dot shift pattern. The shift pattern was changed in 1967, so if you have an original Green Dot Cruiso, the ONLY C6 that will work without modifying the shift pattern is a 66. Hard to find and one year only.

If you can find a 66 C6 Green Dot valve body, you can swap it into a 67-69 C6 and make it work. It MIGHT also be possible to swap into an early 70s C6, but I am not sure about them as starting in 1970 Ford made a LOT of changes in their automatic transmissions.