Toyota Repair: 1996 4runner valve adjustment, 4wheel drive, toyota 4runner

Question
I have a 1996 toyota 4runner limited w/ 4wheel drive and it has 123,000 miles, engine 3.4L 5VZ-FE. While on the interstate a heater hose blew and my engine overheated and blew a head gasket.  I took the heads to a machine shop while replacing the gaskets and had them pressure tested and resurfaced.  I put everything back together and it runs fine except the valves are now making a loud tapping.  I was careful to replace bearings, etc. back into their original places.  I took it to a shop to have the valves adjusted and they quoted me 2000.00 because they have to take the heads back off to adjust them, is this correct?  Is there any way that the valves can be adjusted while on the engine and roughly how much should this cost?

Answer
There blowing sunshine up your skirt.
There a shim and bucket setup.
You measure the clearance, pull the shim out and measure the shim, then select a shim that is the size needed.
Sounds simple, but you need a shim kit at the ready, so not a job you can do yourself.
The bucket can be depressed with a special tool and the shim pulled out with a magnet  THE HEADS DO NOT HAVE TO COME OFF.
Find another repair shop.

Mike