Depends on what you think is difficult. I'm not 100% on this but I would assume that the Valve cover gasket replacement will require removal of intake manifold parts but hopefully someone else will chime in who's actually done this.

As for the main seals, for me I'd say it's difficult. From what I've been told you'll need to disassemble the top end down to the crank shaft to access the seal.

Off Roader
98 Montero with the Winter Package
89 Montero minty clean and reserved for overlanding trips or Cars and Coffee events
96SR (3.15:1 xcase, 35's) gone to the rust gods
96SR Build Up Thread
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