Take the Rocker cover off. Plugs out, Heaps of CRC or WD40 or something similar down the plug holes. Wind it over a couple of times by hand. CRC will squirt out the plug holes. Tip the motor over and drain the rest of the CRC. Check the colour. If it's rust coloured you may need a hone, if it's milky white you may have some oxidation on top of the pistons (Having said that if the pistons were oxidised it probably wouldn't turn) however if it's turning by hand then you maybe cool. Check the valves for movement and any signs of rust around the valve guides. Some of the valves will not have moved for 5 years and the springs have been compressed all that time and there may be some rust buildup on the valve seats. Not a big deal, gods willing the seats will get cleaned after you start it when the rest of that CRC gets blown out the exhaust. A bit of oil poured down into the camfollowers won't hurt either. Have a look inside the intake manifold for any signs of condensation buildup. Before I start them I like to put a squirt of Moreys top end lube down the plug holes just as a bit of insurance against sticky rings.
Then like SloNLo says wind it over with the plugs out to get oil pressure up. I also like to wind them over with the plugs in but with the coil lead disconnected and the throttle wide for about 30 seconds, this cleans the old oil out of the galleries and cleans out any remaining crap in the combustion chambers and manifolds. Do a quick compression test to make sure all the valves are seating and the rings are sealing, but mainly that it's all even. 140 psi will get the old Rootes started.
A drop of oil on the points cam never went amiss. and a quick check in the carburettor float bowl for lead oxide dust and zinc oxide crap, just to keep it away from the jets and lastly make sure the float valve and the accelerator pump piston is free.
If the motor was drained of water early on you shouldn't have too many issues, there will be rust but a good coolant system flush will sort that once its up and running
