[kdavies3]

Without hearing the noise it's difficult to say.
If it's big ends you may be able to change the shells without removing the engine.
Does the Sumo chassis allow you to remove the sump with the engine in?
A horrible messy job but do-able.
Does the noise sound like it's top or bottom?
If you rev the engine can you feel any vibration through the clutch pedal? only with a hydraulic clutch.