Geoff Dellow has the following for your vehicle:
NISSAN PATROL (1980 – 1987) MQ–MK Petrol or Diesel 4 or 5 Speed
• Chevy V6 & V8 into Nissan Patrol
• Holden V8 253 / 308 into Nissan Patrol
• Ford V8 302/351 into Nissan Patrol
• Chrysler V8 – 273 / 318 into Nissan Patrol
• Chrysler 6 cyl 245 – 265 into Nissan Patrol
• Falcon 6 XR – XF into Nissan Patrol
• Falcon 6 EA and on into Nissan Patrol
• Commodore V6 3.8L into Nissan Patrol
Give them a call. Also try
Mark's but I am not sure whether they do the conversion you're looking at. Don't forget that if you have them, you've got to get power steering, air con, etc working and of course your alternator.
Then there's exhaust, fuel, coolant and air connections, hmmm... not a hell of a lot really if you don't mind fiddling around a bit.
Jason