What exact model L2650DT do you have? It does sound like a clutch thing. But before you split it, there are three different clutch versions on the L2650. The first version, L2650DT, has a dry two-stage clutch. The second, L2650DT-GST has glide shift, which has a single stage dry main clutch but also has a hydraulic shuttle (reverser). The third model L2650DT-WET has a fully hydraulic main clutch (larger and more robust than the hydraulic pack in the GST.) Are you confused yet?
If a dry clutch machine doesn't move, engine speed doesn't usually matter and it may well be time to dive deep. But if a GST or wet-clutch machine doesn't move, there are some hydraulic pressure tests to do first. Sometimes the fix doesn't require splitting the machine. Good luck, Dick B