It does help, macs has 2 different pressure plates listed. A 1 7/8 and a 2 1/4. Thanks!

 

Updating here, my understanding is that flywheels are the same for either clutch, 10 or 11" - but bolt pattern is different. I am upgrading an 8BA car motor to a truck. I am stuck on the 2 1/4" vs 1 7/8" pressure plate release fingers question. I know not whether it due year/style of trans, or 59A flywheel (cast iron) or 8BA flywheel (steel). Or possibly due integrated bell housing vs 8BA removable. Anybody got insight?

Macs lists the 1 7/8" for all 122"wb up to '47, both for '48 and up.

I got an 11" flywheel (to swap my 10" bolt pattern) but now stuck on which pressure plate to use.

Feel a bit like franenstien on this. Motor was in a 52 F3 - but transplanted from unknown car. It is going in a 46 tonner panel.

4 speed spur Trans from 46 was rusty junk. Using case to keep numbers matching but gears/internals swapped in from the 52 F3 original trans - all but the e-brake match up - wow!

 

If you don't have a big truck that you're going to use as a big truck or you're not going drag raceing you don't need the 11" (Which also must be matched to the bellhousing)
So now you're down to a 9 or 10 inch - Measure the bolt pattern and go by that - also make sure that the spline count on the clutch disk matches the trans input shaft
Don't try and complicate something that isn't complicated.

 

The bolt holes in the flywheel determines what size clutch fits.Measure the distance between the two holes in flywheel......3" between holes is for 9 1/2" clutch. 3 1/8" is for 1o" clutch. 3 3/8" is for 11" clutch. If the holes are evenly spaced around flywheel, this is for Mercury clutch.

 

Thanks, I'll contemplate your K.I.S.S. strategy.
I'm one who likes the details and one is that Ford Marketing in 1946 was tauting the 11" clutch in these trucks: '44% larger clutch for more service life and dependability'.
Also thinking that as a Parade/show vehicle, the clutch gets maybe more where and tear then if it were back in work/farm service.
Additionally, it is a 122" 1T panel of which all running gear is heavier, harder to get rolling than say a 1/2 ton (17" split rims and tires, 14" brakes, heavy full floating timken rear, etc).
Lastly regardless of which clutch, trying to find out what distinguishes why the different pressure plate fingers.
This in part due my stable includes a '41 Tonner Express, two '46 Tonner panels, a '50 F3 Express, and looking to add a '38/39 Tonner and a '53 F250 to finish the collection.
I'm still going to ponder the 'don't mess' solution