I am kicking around different ideas of how I could achieve this

I have been bitten, hard, with in place upgrades before so I am not really wanting to do this unless its a complete last resort...and even then I'm iffy

Really, the only configuration I have is 1 VDSM hook and about 20 networks. The physical hardware is not going anywhere. Out of my three nodes, I can push all VM's to the other 2 nodes and do a fresh build on 1 node

I am hoping there may be a way for me to do a fresh install of 4.2, export engine config from 4.0.1, and then import it in some way - is this possible? Quick google doesnt yield much and searches for 'export' usually result in storage related results