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Discussion Starter #1
So, I finally pulled my 350 and saginaw out of the lemans and while doing so I started thinking. Is a Muncie m21 a direct bolt in replacement or is there a difference with the clutch linkage. When I looked at the Muncie it does not seem to have the same linkage points for the clutch pedel linkage. Maybe it will come to me when I put it in. In my head I just cant figure it out.

Was anyone ever done this conversion if so, what problems did you run into.
Thanks
 

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im not sure if the input shaft splines are the same. (but i think they are) you shouldnt even have to touch the clutch linkage. just change the trans and not the bellhousing.
 

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67 Basket Case Restorer
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2,717 Posts
The only linkage difference is the shifter. Like Shane said, those transmissions were completely interchangable on the assembly line, depending on engine power. The clutch and all it's related linkage are the same, as is the driveshaft. Take the Sag and shifter out and plug the Muncie with correct shifter in and you're done, UNLESS, someone in the past cobbled something non-original in there...
 

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Discussion Starter #6
There is a bracket that attaches to the saginaw and held in place by a cotter pin towards the front of the linkage. This bracket is a pivot point for the clutch peddle linkage. This bracket does not seem to attach to the Muncie the same way. I will add a pic of the bracket and the two transmissions today.
 

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Your clutch pivot does'nt attach to the block? You might be able to move everything to use the block pivot point.



Or go hydraulic.
 

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67 Basket Case Restorer
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2,717 Posts
There is a bracket that attach's to the Saginaw and held in place by a cotter pin towards the front of the linkage. This bracket is a pivot point for the clutch peddle linkage. This bracket does not seem to attach to the Muncie the same way. I will add a pic of the bracket and the two transmissions today.
That's the back drive shaft to allow the key to go into "lock" position. I believe you need to put the car in reverse, or is it 4th, to remove the key ? You will need a whole complete different shifter for the Muncie anyway and it should come with the correct bracket to hook up the back drive shaft. If you have a shifter on the Muncie now, it most likely isn't the correct one for your year/model. It may well work but you need to get the correct arm for the shaft.
 

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67 Basket Case Restorer
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Yep, that is the bracket for the backdrive shaft that you show in the last pic. If you had to put the trans in 4th to remove the key, you will need to get a bracket that works with the Muncie trans. If you didn't need to put the Saginaw in gear to remove the key, then the shaft had already been over ridden and you won't need the bracket for the Muncie.
Also, the Muncie has a Super Shifter, which will require major floor butchering to use and if console equipt, the console will need to be removed. I suggest calling Hurst to see what Competition Plus shifter your year and model would take and look for one. The correct linkage kit would have the back drive bracket then too.
As a side note, the throwout bearing on the Muncie is backward, if you hadn't noticed. Don't try to install it that way.
 
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