Which gaskets for 5hp briggs

Here's the story with this engine. This was a methanol cart motor and Apparently if you placed in a race they took your motor apart to inspect it. It's just a bunch of parts right now but I'm going to try my hand at rebuilding it. It's been apart since the 90's just laying in a box. How can I tell which gasket kit to buy, is there a number on the block or are all the 5 horse flathead briggs the same kits. 20210817_170511.jpg 20210817_170525.jpg 20210817_170538.jpg 20210817_170551.jpg 20210817_170703.jpg