Craig - In doing a quick search on the web, my search results indicate you need HT-761 lifters (0.989 to 0.990 inches diameter) for a '59 235.
HT-817 specs indicate those are 0.842-inch diameter, which is the standard diameter for Chevy small block and later 230/250 inline 6's.
It's the right cam for 235/261 engines, but the wrong lifters.
