Take the upper end of the line in pic #2 and move it outward to the junction of the of the shock box and the lateral tube. This will provide both vertical support of the rear "suspension/diff box" and lateral stability also. Here is what I did, with an RX7 rear diff:
Attachment:
frame with roll bar.JPG
In my build, the lower short tube also tied to the suspension/diff box was intended to provide stabilizing the outer skin. My frame started out as a CMC chassis that I converted to IRS, I think before anyone had plans for the IRS published.
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Chuck.
“Any suspension will work if you don’t let it.” - Colin Chapman
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