Surprised nobody has mentioned weather a 064 recoil will work with the 1201 flywheel.
I know it's been mentioned on other chainsaw forums. You might try a search.
If the link is verbotten on AS can a Mod remove it. I cut and pasted the post #22 below the link.
https://************/threads/the-mighty-stihl-064-and-early-066.17835/page-2
"Good thread Huskyboy,
I got three 1122 shelf queens 1986 064, 1992 066 Mag red light and a 1997 066 Mag (last of the strong 066's before they went EPA detuned in 1998).
The two 066's I OEM rebuilt a year ago and had offers $800 CDN for each of them, I couldn't sell they have since been serving my tree service.
The '92 066 is running a 064 flywheel, rewind housing, top cover and a 268XP top handle. No dogs and replacing the dual outlet muffler with the '97 gutted standard muffler saved almost a lb. The '92 066 weighs almost as much as a 046.
It's my ripper saw with 20" ES light.
The '97 066 is a real surprise to me, I thought my older red light was the stronger of the two. But after its rebuild and running 28"-36" it's a real torque monster. I'm very happy to have the last year model of the strong upgraded 066's.
Oh BTW my '86 064AV with race ported cylinder and 084 carb I'm not sure yet what to do with it."