FWIW Ryobi with clutch ( you can rotate cutting w/o turning engine over) will yeild a long shaft engine; without clutch will be a short shaft engine. I would imagine that new ones sold in CA will have only a single needle for carb adjustment. You will probably end up putting larger carb on it anyway...
I believe the long shaft when converted is actually shorter in OAL ( firewall to prop) due to the components you have to use.