Drum Switch wiring for a 120 v Dayton motor

This may be a tired subject but I have not seen an answer to my question. A friend just bought an older Southbend lathe but the owner was just running it in one direction even though it had a drum switch. So he tried to rewire it for reversing with no success so he brought the problem to me. Ha! I have it running in both directions but I am not happy with it because it seems to be vibrating more than I would think plus I was not convinced the wiring was right. I have attached pictures but I don't know if they were too big to show on this first post. The motor wiring does not have the typical T1 - T8 labels but just colored wires with stake-on going onto numbered terminals 1 thru 5. Reversing permanently in the motor is easy by just reversing the Red and Black wires but doing that with the drum switch is another matter. My question is when you take the Red wire off of terminal 4 there is nothing from the drum switch to come back and go on the terminal. I think I have unbalanced the winding which is causing the vibration. Any help would be appreciated. If the pics don't show I will shrink them and resend.

Dayton is from Grainger....so I Googled it and found this.

https://www.grainger.com/ec/pdf/2X440_1.pdf