[dodgeboy12008]

I just received a 5700 vortec engine. It is almost a long block but I am missing the oil pan and the flexplate. I am wondering if i can just order an externally balanced, one piece rear main seal flexplate to use with this engine or does the plate actually need to be balanced with the rotating assembly? My other question is, can I run the old style oil pan or to I need a late model specific pan. Thanks for any help.