Hi all, I am in the process of restoring a series 2 that has been sat in barn for 30 years. I haven’t attempted to start the engine yet, any advice on how to recommission it to test the engine is working? Coolant was drained when stored and there is oil in the engine. Any advice welcome!

I'd take the plugs out, squirt a bit of oil in the bores and then turn the engine over by hand a few times. I would change the oil and filter before attempting to start it and (obviously) refill the coolant. If its a petrol you'd need to check/clean the points and dizzy cap and probably swap the leads. If its a diesel you might have to bleed the system and/or replace the diesel in the tank as diesel can become contaminated over time.

For the fuel, use a container suspended above the engine and temporarily plumbed in to prevent all the crap in the old tank and fuel lines causing a blockage. Id try turning it over on the starter but without the coil connected or without fuel to prevent it starting while the engine is starved of oil.

Col

Before you try and start it, I would assume that the carb jets will be gummed up or corroded. You would probably save a lot of wasted effort by splitting the carb and cleaning / clearing the jets.
Clean up the points with some emery paper and check for a spark.
If you have a spark and it won't run, dump a little petrol directly down the carb.