There are a number of ways to accomplish the compression of the Clutch Diaphragm Spring.
Some of which rely on the clutch adjusting screw (ramp assembly stud) to pull against to compress the spring.

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3“ PVC cap w/ 5/16”x24 bolt or all-thread, coupler, nut and washer.
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However, if the pressure plate is cracked / broken or the adjuster stud can't be otherwise used, below are some other ideas to compress the assembly.

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Also, here is a commercial compression tool modded for use without the adjustment stud.

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Here is some out of the box thinking with a used pressure plate placed under the commercial compression tool.
This essentially moves the pressure point over the tips of the spring instead of compressing from farther out on the spring.
So the tool now compresses the fingers first giving some initial room between the fingers and the rest of the spring body.

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