Nissan laurel manual pdf

SOURCE: diesel auto to petrol manual

I think that you can buy another car for what it would take to do that conversion.

Lets' see off the top of my head.
carburator
manifold
new heads to accept spark plugs?
new body control module
new engine control module

then keep in mind that even with all the above it still might not work because you may need proprietary parts only made for a gas engine, and you have a diesel. An engine swap may be doable but I ahve never heard of it working out in the end.