Neither of these are of any use on a Gen I roller. If you're going to install the OEM roller arraingement into a roller block that originally had a flat tappet cam you will need the OEM style lifters, the dog bones that align the OEM style lifters in pairs to the camshaft's direction of rotation, the spider that locates and keeps the dog bones engaged to the lifters, the OEM camshaft thrust plate note that there are two different center to center spacings of the thrust plate retention bolts you need to measure your block to order the correct part and correct pan head bolts to clear the cam gear. Further, the OEM roller cam takes a different timing set, this is usually a single row roller chain, there are differences between what will fit the pre 1996 Vortec and what will fit the 1996 up Vortec. There are some aftermarket twin row roller chain sets, these require a spacer or multiple gasket buildups to get the timing cover to clear the chain and gear depth. The 1996 and up Vortec uses a different and plastic timing cover than the earlier OEM roller engines, these can be interchaged with some minor effort.
Jessel sells a kit that replaces the spider with a stud that passes thorugh the dog bone (a hole that does not exist in the OEM part) which eliminates the spider. Not cheap but effective.