cast crank converter question

so i got a 440 off of a guy that broke a rod and trashed the block, i got a bunch of goodies off of it though. it was a cast crank motor with l2295s on ly rods. i got the converter and flexplate too. my question is how did he go about balancing it, its not the b&m style flexplate for external balance and the converter doesnt have any weights welded to the back. also if you guys had any information on the converter. Thanks a lot