I've got several issues with my 1985 6.9L, id really appreciate some help and feedback asap. Its my only vehicle.

#1
Engine has a slight knocking sound at idle. Very persistent, I'm not entirely sure if its rod knock or fuel injector knock. Its not very loud, gotta be closer than 20ft to hear it. Any tips to check this out before i purchase new main and rod bearings with a crankshaft. it also gets very random after i start driving it around but when it does knock its very loud.

#2
Truck has a MEAN leak from the front seal on the oil pan, i know this is an easy fix, just gotta replace the oil pan gasket, but is there any super easy and simple way to change this without pulling the complete motor out?

#3
Does anyone have a Banks Pyrometer gauge? I just want to know how accurate the gauge is, it reads about 570° after driving around at 45+ for awhile. Then just drops down to about 150° after its been sitting enough to completely cool off.

#4
Anyone have any suggestions as to what injectors i should get if they are the knocking sound culprit?

Really appreciate any help i can get guys, trucks my only transport for the moment and i really need to get these issue straightened out asap.