Top end 5.3 please advise

[RestoreAmerica]

Hello,
I am a 67-72 Die Hard.
I recently picked up a 2000 Yukon with a 5.3 and posted in that forum.
Very little response or activity. Obviously a gear head is a gear head. I am just looking for input.
Here is what I posted.

Hello,
I acquired this vehicle and it appear to be worth fixing.

Bad head or gasket. I just ordered a set of remanufactured heads.

While I have this torn apart, what else should I do to the motor.

Vehicle had noisy lifters but also had bad head gasket or cracked head.

I don't want to spend more than needed but don't want to tear it apart in 6 months to replace something I could easily replace now.

I have not gotten the heads off yet. Almost there. I decided better just purchase heads for $300 than to just put gaskets on the old ones. These are the head I purchased http://www.ebay.com/itm/201358045312...%3AMEBIDX%3AIT

Would you replace the lifters or just clean them?

Any advice is appreciated.

Thank you!!