"Great pics that resolve chain-stretch measurement technique off the flywheel once and for all." ----240DieselDog

This is on the other end from the flywheel.... and it does not resolve it because the Factory Shop manual specifically says to use the dial indicator on the number one intake valve opening method of checking chain stretch anytime there is a performance complaint... a method designed to zero out some other wear factors which can be extant on an old engine... and check it against what the engineers who designed the engine were shooting for with regard to actual engine/chain performance....