Knielsen,
The improvements are really remarkable, but from what I see on the photos they are not just related to ground re-wiring.
There seem to be several parts that were changed/upgraded.
I could locate the Acurus 250 schematic here, so it would be interesting to list what you did change, if possible.
The comments by Kaj about the surprising results by using thinner wire for the power lines also deserve an observation.
The improvements are really remarkable, but from what I see on the photos they are not just related to ground re-wiring.
There seem to be several parts that were changed/upgraded.
I could locate the Acurus 250 schematic here, so it would be interesting to list what you did change, if possible.
The comments by Kaj about the surprising results by using thinner wire for the power lines also deserve an observation.