The kit contains all the hardware, springs, retainers, locks and shims, and you reuse the stock locators. If the heads are used then I would replace the valve seals while you have the springs off ( part # listed previously ).
I check with Crane and those springs set at 1.80 install height will have no problem with you 544 lift.
As far as Rockers, there are two basic types for our cars, Self-Align and non SA. A self Aligning has the body of the rocker designed so that it used the tip of the valve to keep it centered. This is good, but with certain retainers or very high lift cams the rocker body can actually hit the retainer. This could result on all kinds of issues up to a catastrophic failure!
A NSA rocker has no such prevision, so a guide plate is installed and it uses the pushrod to keep the rocker centered, in this case you must use a hardened pushrod.
hardened pushrod are stronger and a good upgrade with SA rockers. No need to go extreem with the $100+ ones if you don't want. Comp makes a stock replace hardened for about $40.
The pic below shows the two types of rockers, you can see the SA rocker on the left the roller is above the rocker body and the two guides ( that look like washers on each side of the roller ) keep the rocker centered. The NSA rocker on the right has no such prevision.
The pic below is the guide plates. They install under the rocker arm stud and extend out around the pushrod to keep it centered.