That was quick work.
Trained as an aircraft mechanic in a production shop. Chunk job into bite sized pieces, fix/build/repair, put back on, adjust, move on.
These are simple machines. Air, fuel, spark in the right order at the right time. Follow the manual, don't overthink it, improve where you can, and move on.
(I took delivery of 693R in late March 07, decided that it had to be torn down to parts in April, started building inventory of replacement (including a frame), dropped engine into new frame july, built up suspension and bits, dropped body on Aug 18 '07, drove around the block 4 days later. 3291R is in a bit better shape, so it's not a rebuild as much as a resurrection.)