EA Timing Guide Replace

[Melton-South]

Hello All.

In process of getting the head of a friends 1991 6cyl EA checked and reco'ed, and noticed the chain guide on the passenger side of the engine is broken off. (This is the one which bolts to the head).

I have had a few friends tell me the entire engine has to come out to properly change all the guides, including the one on the inside of the Timing Cover.

Is this correct, and has anyone successfully changed all the guides without removing the engine from the car.

Thanks.
Greg