I would recommend checking bearing clearance before installing the new rope seal. Also the new rope should be worked into place, hard to do with the crankshaft in place. The rope in the main cap can be worked in. With things all set up properly the motor will turn pretty hard. Just make sure that not to tight that it will burn up friction. I would also recommend finding a NOT main seal or a Best Gaskets seal. Most other brands will leak.
Don