Need some advice on rebuilt heads that have been sitting.

[1ton-o-fun]

454 Vortec heads for sale. Machine shop rebuilt the heads approximately 10 years ago. Been sitting on my shelf since -were never installed after freshening them up. $___.

Done.

 

[Pinger]

Is there such thing as an inexpensive tool for removing the valves? I don't really want to buy an expensive tool for one set of heads. I have no idea what I should be shopping for.

It's usually possible to improvise. If you can create a fulcrum pivot point for an open ended spanner, the jaws can bear down on the spring cap leaving room to extract the collets.
Another method is restrain the valve at its head and place a tube over the valve cap and whack with a hammer. The collets will usually jump. The bought version of that has a magnet in the tube to catch the collets.
See pic below of improvised tool used on a very cramped OHC head. It is 'pivoting' around a bolt and nut inserted through one of the head bolt holes. Reassembled with the same tool.

You must be registered for see images attach

 

[454cid]

All of the major parts stores that have rental tools have them.

Oh, I didn't even think about that.

 

[LC2NLS6]

And the rentals are usually free as you get your money back when you return them, pretty sure they still do that.

 

[Erik the Awful]

I don't know if the lever tool works as well on 454 heads as it does on 350 heads, but this, a cordless drill with a 9/16" socket, and a magnet make short work of removing the keepers for only $10.
https://www.summitracing.com/parts/...8rBYByEsLxwFQ5ioVVKNbcWJSzPvMJHRoCgAIQAvD_BwE