Aftermarket gauges - Holden/Isuzu 4JJ1 (3.0 TDI)

I have used Isspro gauges, not the cheapest, but bloody good. EGT gauge is colour coded, so you don't have to worry about what the actual temp is, if it is in the green it is fine. I have three others, water temp, boost and trans temp. I also have a block temp and low oil pressure alarm in one unit and a low water level alarm.

Seeing it is 08 it has done well without gauges so far it seems.
Depending on where you locate an EGT sensor the pic above is green until around 1000F which is 538 C. Sort of ok but I wouldn't like to get that high seeing if the Probe is around 120mm after the Turbo the PRE turbo exiting the cylinder temp will be close to 700C +++ which is too high so less than that is desirable. You are correct most don't have a probe. I have a Scintex digital which I fitted with alarm and it is set to 450C.
Trans temp can be accessed via a good brand of OBD gauge and usually selectable to be read along with other info at the same time, ie, water temp, boost level to read economy of throttle. Push harder more boost less economy.
The Engine oil is cooled via the heat exchanger built in the side of the block so really no need to know oil temp, just use a good brand of oil. Pressure of oil might be handy but unless the engine or pump is stuffed you again have no control over it. Water temp via OBD works well as above.

A pressure sensor in the radiator system or level detector can avert disaster. good idea!
A block temp probe can be purchased off the net and a 12v temp display unit (just a circuit board with settable digital display) can be added to alert of any over normal temp if water disappeared. Banggood site #1416341 can be used to detect engine block temp via a NTC sensor (negative temperature coefficient) and turn on an internal relay using an attached alarm of your choice. $9:23 + postage + tax etc around $15 to your door. Make sure you select the 12v version and not the 240vac version.
Hopefully some info to consider.
Cheers

Thanks John and RMD.

Yes it has done well so far, but it's right on 300k and I've just had to replace the injectors (and possibly the ECU, still waiting to hear). This and a couple of other circumstances have blown any plan of a new rig this year, so I need to live with it a while yet. I do a bit of towing, and considering all the dollars it has just cost me I'm happy to put a couple of hundred more into some gauges so I know what's going on under the bonnet.

I've got a replacement stereo than runs Android, and I'll run Torque or similar on that to peak at things from time to time, but I've decided I want some permanent analog gauges to watch the important stuff regardless of what the Android is doing.

RMD is your engine the same as mine? I'm curious about mounting the EGT sensor, is there a convenient location before or after the turbo (it is still at the mechanic so I can't look myself)? I can probably tap a hole in the manifold if I need to but it would be nice to avoid it.