Usually you'll find that if the air cleaner is OK and the carby isn't blocked it really doesn't take much to start a two stroke.Just be careful with the Twin they do have problems with rings being destroyed.Just make sure on that one that there isn't any crap in the cylinder.As your not going to find any spares for it,any time soon.Very very hard to find parts for and even when you do it's come from wrecking another mower to get them.It's hard to tell from your photos (and due to the colour change),but I do believe the Twin is what I call the 2nd version of the 500 twin and has the (Most likely) 1st updated engine on it with the carby heat shield on the base.The VC-160 would be the Mark II from 1971.If it has the original engine on it the number should be 5271.I'm just not sure I like the blue bases and the red dress cowl on the VC-160.Also the VC-160 doesn't have the original wheels on either.They are a later version of them.I still think you did very well though,wish I could find scores like that.Well done I say.