Nothin but a Ford

1996 F-150 4x4 regular cab 302 automatic. I got the truck from my father after he died. It had a transmission shudder when I took it, and I would assume it had been there for a while. Dad was a mechanic, and while he was praised by many as a good one, he was an example of the old addage, don`t buy a mechanics car. He only did the repairs on it that he needed to keep it going. While I have all his tools, and can do the work, I don`t have the knowledge or experience. After visiting this forum, I found out the cause of the shudder, and after changing the fluid, the problem seems to be cleared up. The oil and filter was never changed, as the factory dipstick plug was still in the pan after 238000 KMs. Even when my father was alive, 4 years ago, the flexplate was cracked. I have babied it up till now, but it is getting worse. I know flexplates crack often, but could the converter shudder have caused the crack, or is something else out of wack, bad input shaft bearing....I was planning to hit the junk yard for a flexplate, and where I have no hoist, no torches, I live in Canada= winter= salt= rust, so I am going to take it to a shop to get it changed. I read some where that depending on where my 302 was made, that the pto end of the crank can have a different number of bolts. Is this true, if so how can I make sure I get the right flexplate so the truck is not stuck on a hoist while I run around looking for a part.