Rocker shafts, spacers, hold downs

I’ve got a 73 318 that I purchased in pieces and need info on the rocker assembly. Between the rockers are spacers that I don’t have on my other sbm. Also, I don’t have all the hold downs but the few i have have upturned sides unlike my other sbm. With this setup can I use the regular hold downs that don’t have the upturned sides? Or are the upturned sides a requirement when using the spacers with the rockers? Also, the shafts don’t have the notches on the bottom as do others. Any help is appreciated. Thanks