PItman shaft seal installation advice

So,as I figured,the old "be prepared" motto should be heeded. I dont want to start work on this only to be stymied by the blow out method not working. Harbor freight sells a seal puller for 8.99 or so,maybe I should pick that up too. What size wood screws did you use?

They are "self tapping" screws outta my bins, not sure the size, take the replacement seal with you to help decide, thin, and sharp.