Interesting question. This has been discussed before here. As I recall, the spring perches/shock locations on later R/E's are in a slightly different location than the torque-tube axles. So when doing the swap, sometimes the newer R/E ends up shifted. I'm just parroting info, one of the guys who've done this swap will be along shortly to explain it in more detail.

chip

Preaching the Hot Rod Gospel according to the 4-stroke apostles:

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