This is my first post.....I have just purchased my 1969 Chevy stepside shortbed. 6 Cyl with a 3 on the tree. I want to lose the 6 and go with a 1969 vintage 350 engine. I would also like to add a 700R4 transmission. My neighbor has a 1993 700R4 out of his 4.3 blazer( for $50). What kind of road blocks and surprizes should I expect. What is the lock up converter I have been reading about? Lots of questions.......I need hellllllllllp. Mike