I positioned the front so the middel belt pulleys are 597mm apart. With 18/26 gears I can then use the HPC gears HTD3 3mm Pitch belt 1263mm long.
The gearbox is also from HPC gears Its the HPC-GBK-101. It came packed with grease so I washed it out and oiled it with light oil. Its only supposed to be rated to 3600 rpm and I'll be reving it to 60,000 rpm. LOL. Lets see what happens