fronts are 4''rims with 6 bolts to the hub plus the bolts to bolt the rims together. the rears are 6''rims with three bolt type plus the bolts to bolt the rims together, sorry only pics I got
Your rims have a larger bolt pattern than any modern racekarts use. Van-K still makes 4" split rims, they mighta made your karts original rims back in 1960. You should contact them asking if they have your bolt pattern in stock, or will drill some rims to your pattern:--> http://vankwheels.com/van-k_wheels_v8c_010.htm