Congratulations mate. Whilst this thread has been quiet, I tried the diff merging thing. Its really close but I just dont have the right bearings to fit the crown gear side of the diff and the GS drive shafts are slightly longer than the HPI ones meaning the neck of the shaft is rubbing on the cross shaft inside the diff. I am trying to solve it but I am running out of possibilities fast. The most frustrating bit is that the CEN diff housing/bulkhead will fit perfectly![:@]