I don't think it is too hard to build a test stand to verify the engine can run and condition. I built the stand in the pics below before putting this fresh rebuild in my 914. 2x4 and and deck screws with some wheels so I could move it around, total cast around $20. I used the oil tank that was going into the 914 (you will need to get on to do your conversion). Looks like your engine has carbs so easy to get a electric pump and regulator with correct pressure. I used a motorcycle gas tank I borrowed from a friend but was going to use a small boat tank. All the electrical you need for it to run is for the ignition and some jumper wires for starter.As many have said if you lube the cylinders up well and rotate. Crank engine until you have oil pressure ( can measure with multi meter if you don't hook up gauges). Run it for a while and then check leakdown.
john