1985 Merc 200hp V6 Outboard Unused for 2 years

I picked up this engine for cheap. Where would you start at diagnosis prior to starting. It has WH28 carbs and complete oil injection system.
The shop I bought it from said someone had sent this engine to them on a pallet with the intention of having it repaired. The shop owner said after he received the engine, he never heard from the owner again. I have ordered gaskets and needles with seats for the Wh28's and plan on using them on another engine if all else fails. I know I need to fog the cylinders and check compression first thing. Oil injection system maintenance is something I have not dealt with before. Any advice on getting it running would be appreciated.

Get a service manual. Check compression, change fuel pump diaphragm and fuel filter(s), get new fuel line and squeeze bulb, inspect fuel lines internal to engine for cracks and replace as necessary, drain and refill the lower unit, replace the impeller in the water pump.

Mix your fuel 50 parts fuel to 1 part TC-W3 2 stroke oil...walmart has Pennzoil premium plus at 5 bucks a quart. In the manual it tells you how to check the operation of the oil injection...basically, measure the oil in the tank, run the engine for specified period at specified RPM. Measure the oil at the conclusion of the test. If your consumption meets the numbers in the manual you are good to go.

First thing to do is run compression test and inspect cylinder walls. This is a chrome bore motor and if chrome is scuffed or peeled block is not worth repairing.