I got a little confused re the sensor orientation because the original (prototype?) article shows the control board mounted on the base of the unit normal way up but the final aricle shows it mounted upside down under the cover.
Not sure if there is a difference in the firmware to accomodate the change but I guess it will be easy enough to tweek.
I have sourced some surplus 450Watt 24Volt 550RPM motors from Oatley Electronics in Australia for $129.00 AUD each which I think will be closer to the design criteria than the wheelchair motors that I already had.
Thank you Brian for the heads up regarding the chips on carrier boards, Sparkfun is a very interesting site, where have they been all my life?
I am currently analysing the firmware and note that there are some diagnostic LED sequences, is there a list available with inerpretations.
My next step is to sloder the SMD's to my board - a new experience for me but there have been some excellent articles in Elektor recently so confidence is high!