3 on the tree to sm465 conversion questions

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Jamesz

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Correct. Cut the opening so that there is still a 3/4" to 1" flange to attach the new trans hump. You can simply use self tappers, or drill larger holes in the base flange and use threaded j-clips, or install nutserts in the base flange for bolts to thread into. Having the removable cover is super handy too.
Gotcha! last night I ordered the cover from Auto Metal Direct so I will see when it gets here.
 

Jamesz

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Correct. Cut the opening so that there is still a 3/4" to 1" flange to attach the new trans hump. You can simply use self tappers, or drill larger holes in the base flange and use threaded j-clips, or install nutserts in the base flange for bolts to thread into. Having the removable cover is super handy too.
One more question. What size bolts do I need for the sm465 to go to the bellhousing? I have been reading different answers. Would you or any others have information/pictures or such to share? Thank you guys so much for the help!
 

bucket

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One more question. What size bolts do I need for the sm465 to go to the bellhousing? I have been reading different answers. Would you or any others have information/pictures or such to share? Thank you guys so much for the help!

Just off memory, they are 1/2" x13 bolts, maybe 1.25 or 1.5 inch long. I can go out and check to be sure in the AM, if I remember.
 

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Thanks man! So do I would assume I would need nuts for the bottom two? The bellhousing I got has threads on the top mount holes but none on the bottom. I don't know if I got the wrong one or not.
 

bucket

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Thanks man! So do I would assume I would need nuts for the bottom two? The bellhousing I got has threads on the top mount holes but none on the bottom. I don't know if I got the wrong one or not.

All four holes should be threaded.
 

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That's weird. I was thinking about it today when I got to the shop so I grabbed some pictures. Do you think I should look into maybe threading these holes?
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Turbo4whl

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That bell housing with open bottom has room to put nuts inside. Older style, will probably only fit the 11" clutch. Advantage is you can use stover style lock nuts. Will not vibrate out.

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You guys are actual lifesavers. Thank you soo much!
 

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Welp. I had ASSumed that you had the typical aluminum bellhousing that was used in the squarebody trucks. My bad, lol. I'm guessing you will need longer bolts for those bottom holes then, maybe 2". I've never had one of those older bellhousings.
 

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Welp. I had ASSumed that you had the typical aluminum bellhousing that was used in the squarebody trucks. My bad, lol. I'm guessing you will need longer bolts for those bottom holes then, maybe 2". I've never had one of those older bellhousings.
I thought I did too lol. I've never worked on much gm stuff mainly toyota and motorcycles. So I'm not familiar with all the different styles yet. So far so good though! These trucks are super simple.
 

Turbo4whl

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You want to measure your bellhousing. Newer style is 6.29" trans flange to engine flange. For many years engines had a single engine mount in the front and used a mount on each side of the trans bell. This is how the many 6 cylinder engines were mounted. Your bell has those mounts.

As more V8s were installed the mounts were switched to 1 mount on the back of the trans and 2 mounts on each side of the engine. You can use that bell as long as the front to back measurement is correct, also the diameter of the rear hole needs match the trans. I think you need 5 1/8" hole.

Squares came with this style bellhousing:

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This will fit a 12" clutch.
 

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