300/440/550 stock 88 550sx with 44sbn, need jetting

[oldschool440]

On my buddys 88 550 he has a stock motor with only an old school K&N air filter.

Could i get some info on
Good N&S size
jets
spring

also will he need a throttle drum on that carb or will the stock 550 throttle work.

Thanks
Mike