So what am I looking at exactly

those are std 340 springs, i think someone just changed the rockers over. very common, the std hyd rockers are not very uniform and with adjusters you can get much more precise. but the engine looks to have been rebuilt? so could have a mechanical cam.if you look at the front of the motor where the head meets the block, can you tell if the head gaskets are aftermarket? its clear some of the other gaskets have been rtv'd. if it were mine, i would make sure it runs good, is safe and i would destroy tires at will with it. enjoy