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Thanks, JC. I think I am finally happy with the front leaf spring mounts, so I fine tuned and cleaned them, then plugged all the spring eyes with styrene tube. Once the superglue had set on each plug/eye, I drilled a .020" hole for each bolt, and now all are a snug fit, with minimal play. With the front leaf springs and brackets in position, I test ft the GMC Astro front beam axle and checked for engine clearance again:

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That should be plenty of clearance. :) 

I might end up replacing the Astro axle with a scratchbuilt brass axle, but first I need to re-install the rear suspension and set everything on the wheels and tires to check how everything sits. It's been a few years and suspension changes since I last checked the stance, and a preliminary test fit of the rear leaf springs on the frame shows I need to adjust the curvature of the top two leaves for a better fit. I also need to either commit to soldering the alignment bolt to the rear leaves or find a longer bolt which can be removed and reinstalled as many times as desired, the latter being my preferred choice. I re-checked the width of the front axle with the wheels, tires, and backing plates in place against the cab, and everything looked good, so no issues there.

Edited by Casey
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Digging into some Hendrickson rear suspension reference material clarified the problem with the rear spring bracket, so I need to add a "hump"/half round piece of material inside the bracket's slot for the top leaf to rest on. I probably removed the material when I started opening up the slots way back when to fit the springs, so should be an easy fix to get the rear end of the spring back into the proper position, allowing the spring to sit more level. 

The factory service manual I'm using is for GMC trucks, but the Hendrickson RT suspension appears to be exactly the same as that found in the AMT GMC Astro/Chevy Titan kits, so I will follow it for the most part. There does appear to be a little bit of ambiguity regarding exactly what the rear leaf spring bracket looks like, but I think the line drawing without (pic #1 below) what appears to be a pin (shown on pic #2, just above the rebound bolt holes) is correct, as the arched line shows the lower end of the hump in direct contact with the top leaf:

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Also updated the post title...no more Studebabaker. -_- Not sure how many times I read it and never noticed until now. :unsure:

A few more Hendrickson RT suspension pics, for reference:

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A shoulder for the floating end of the spring to ride on makes sense.  You piqued my interest about the Hendrickson RT suspension, apparently the basic design has been used for decades.  Great design and sound engineering never goes out of style. 

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On 3/20/2018 at 3:09 PM, afx said:

Great design and sound engineering never goes out of style. 

Very true. :)

I cut, shaped, then glued the two arched pieces into place, and drilled some new holes for the front spring eye bolt. After looking at the Hendrickson suspension drawing again I noticed the spring eye pivot point is higher than the rebound bolt holes, so that helped level the springs out, too. I still need to fill the old spring eye holes, but it's sitting much more level now:

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On to the equalizing beam bushings...

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Edited by Casey
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Equalizing beam bushings installed and drilled out for the bolts (though technically they should have pins), and a test fit to check alignment and positioning relative to the )now soldered together) leaf springs:

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I also checked the wheel center/spindle height with all axles set in place and the rear is .5mm higher, which is fine for now. I still need to make the spring saddles and I can always add a small shim/spacer up front to level things out. The front tires really fill out the front wheel arches, so a little extra space between them wouldn't be a bad thing, either.

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