It's most noticable when it's getting higher in the rpms, just before a shift. But it's always there now. I only have the stock "idiot gauge" that reads enough/not enough. I was reading around and was looking into an Autometer for a more exact number, but I'm not sure how easy they are to install.
A wet pressure gauge is a no brainer. All you need is a brass "T" fitting at the stock location and feed the tube in through a hole in the fire wall, snug your fittings and check for leaks

h34r: /emoticons/
[email protected] 2x" width="20" height="20" /> . I ran mine in along side the speedometer cable. I'd pull the valve cover and check the valves to see if any are loose or worn. Replacing rocker arms can be done without removing the heads plus 1/2 the stems have replaceable stem covers that wear over time. There is no rocker arm adjustment except tightening to specifications. They make a valve spring compressor that grips the spring and compresses it by turning a large ****. If you go this far, I'd replace the seals, springs, rockers and valve caps. The procedure is as follows (off the top of my head).
1. Remove your spark plugs
2. Bring the cylinder you are working on to TDC (prevents losing the stem inside the cylinder if it gets away, also, it releases the pressure on the valve stems by the lifters). If it does get away, all you have to do is pull it back in place.
3. Using a compressor set to at least 90 lb and a fitting for the spark plug hole, pressurize the cylinder (that keeps the valve seated and sealed so you can remove the rocker arm and spring).
4. Install the spring tool and compress the spring (CAUTION; there are two small grippers holding the spring to the stem, don't lose them).
5 Remove the grippers, remove the spring and seal
6. Take the old spring out of the tool and install a new one (There are two different springs, one for the exhaust and one for the intake stem, be sure you use the correct spring).
7. reinstall the new seal, spring, stem cap, and rocker arm, tighten the nut to specifications, (Off the top, I believe it is 25 ft. lb. but if you decide to do this, I'll check to make sure that number is correct).
Good luck,

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