Oh nice one!
I think you can be hopeful that it will run, given your tests so far.
The really hard to source parts are the plastics and you have all those, so that's great.
As Mickdb1 says, there is a really helpful community, if you can track them down including a fella called Marc in Hull who has a good store of parts.
If you are interested in how far you can push the Elefant obsession, gave a look at Gavin Robertson's site here
www.gavin944888.com
Electrics aside, which can sometimes be a bit 'italian' I think the engines are really well engineered.
Mick, did you attend the Treffen in Aachen about 10 years ago? If so, we probably spoke