I am about to order ER Rockers. What else do I need? I will be getting springs too, but do I need bolts? Gaskets?

Thanks to everyone!

LSx style retainers with the springs
TTY or Re-usable rocker bolts
Valve cover gaskets (may be ok to reuse)

Some rope to stuff in the cylinder so you can squeeze it up to TDC and keep the valve up.
Or a fitting for compressed air.
I used the latter without problems.

Forgive my ignorance, what is the difference or what does this give me?

No sweat.

If you get 90 or 105# springs, the diameter of top of the spring is slightly larger than the stock spring.
So, if you were to use a stock retainer with either one of those springs, the retainer wouldn't center the top of the spring. This can lead to side loading of the valve guides and possibly break them. (I was pics of this)

Also, your stock 3800 retainers are thicker than CompCams / zzp / GM LSx retainers, and will not give the correct spring seat height.

I've used the compressor method many times. It is much better than the string method (ask TJ).

Depending on mileage, you may want to change the valve seals when you have the springs off.

I have a compressor and will use that method. Mileage is 95,000. Seals sound like a good idea!

I've got to sets of stock retainers if you need some on the cheap.

Ed

So far I understand I need (or it would be great to get):

LSx retainers
Re-usable rocker bolts
valve seals
valve cover gaskets

fitting for air compressor to pressurize cylinders
valve spring compressor tool

Anything else?

This is very helpful!

When I did my cam I used a small magnet to easily remove the valve locks. More specifically a telescoping pen style magnet pick up tool.

Not to mention a torque wrench for those rocker arm bolts which are 25 ft/lbs if I remember correctly.

Ed