I went to Kubota Canada's website, 'parts finder', typed in T2290KWT and only ONE hit. Drawing is from the 'HST' section. I wondered what the 'deal' was as the 'layout' is very,very common.
I do the following...
1) remove deck belt and deck (deck goes on bench for cleaning usually....) frees up 'working space' !
2) clamp clutch down to release drive belt tension
3) remove belt off engine drive pulley,maybe loosen guides if need to....
4) snake belt off the 2 tensioning pulleys
5) drop belt of 'small right rear ' pulley
6) loosen the HST pulley guide if needed
7) carefully snake belt off HST pulley.one hand on each side of belt,hold one, push other, belt gets 'bigger' around pulley, and it'll come off.... Once you do this a couple times, you'll get the hang of it.
8) loose belt comes forward,down and out.
Installation is simple the reverse ,so 5-10 minutes. It helps if you have GOOD lighting !