I use one that IS factory.(and stealth!)

1. Take an old fuel/temp/ oil pressure/economy gauge section from a GASSER 126 and transplant it into the 126 diesel instrument panel!
2. Remove needle from economy gauge (remove STRAIGHT up).
3. Replace needle on the ultra thin gauge shaft from where it came, but place it with the needle pointing at ~10:00 o'clock position.
4. Rotate the needle CC and lift/ bend it over the left side stop pin.
5. What used to be the economy gauge (Bourbon type vacuum gauge) is now a boost gauge (Bourbon type pressure gauge).
6. Attach with appropriate hose to "T" in boost line or to the empty intake manifold fitting.
7. I attached the hose to an aquarium gang valve in the boost line to the overboost protection switch so that I could rig a parallel hose and shop gauge temporarily into the cabin in order to calibrate (by moving the indicating needle on the shaft of the former economy gauge).
8. Full travel (left to right) is ~16 psi after calibrating. (I run ~14psi full out uphill). FWIW

__________________
The Golden Rule

1984 300SD (bought new, sold it in 1988, bought it back 13 yrs. later)

Any tips to removing the needle? I can't get the bugger to budge.

The shaft that the needle hub is pressed onto is very thin, so "straight up" removal is important. I use pliers with tape on the jaws now.

Two spoons (with tape on the undersides) as "pry bars" on the needle hub have been used with success.

Be careful, but strong, and good luck.

__________________
The Golden Rule

1984 300SD (bought new, sold it in 1988, bought it back 13 yrs. later)

Will that 126 gauge pod work with a '90 124 300D? Or are the electronics for the fuel/temp/oil pressure different?

__________________
Dale

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1990 300D 2.5 Turbo -155k
2000 E430 - 103k
2014 Jeep Grand Cherokee Ecodiesel 4x4 - 11k
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