I use the ProShock setup on the car and it works great. For a small block you need the 8" 375lb spring. The part number is 8SR375. The shocks on the CR are not MII. We use a longer shock for extra travel. The shock to order for the coilover setup is the ASB550SR. The coilover kit for that shock and spring is part# C-385. These are the correct length,
oil filled, and light valved. They need to be ordered with the S-576 stud mount. I use a bearing on the bottom, part # B210, and the B211 snap ring. You will need spacers for the lower mount to go between the mounting points. The part # is S-100. They may need to be trimmed to fit. I would order tubular lower arms for coilovers. These shocks are adjustable for the ride height and will give a good ride. If you go with another brand of shock you need 4" of extra travel. I would use the cone spring with any other brand. The coilovers with the spring attached at the top of the shock will not clear properly without some modification.
Don