Guy,
I'm sorry to hear that the Modelling Gremlins have made it all the way from my bench to yours in the past several days! I'd say between Steve, Stephen, and yourself the solution is as stated; you need a jig for projects like this! If nothing else it would free up your (we only get two after all......) hands to measure and adjust the several dimensions you are dealing with. The stagger, spacing, and lateral alignment of the main and center cabane struts and achieving wing alignment top to bottom is complicated and you need all the help you can get when dealing with unsecured "free floating" strut mounts. With a Wingnut Wings Kit as an example the strut to structure fitting is beautifully engineered and usually careful assembly allows all the struts to be pre-placed and the upper wing more or less just pops on. With your Vildebeest you have none of those luxuries.
I hope I'm not coming off as "Mister know it all" here but I'd say a jig should be in the revised plan, and possibly a simple version as suggested would suffice. I have two of the things, the old Aeroclub one and a newer Vertigo Jig and I rely on them a lot. I also use Stephen's "simple is better" approach to the jig requirement when it suffices. As you can see in many of my "true confessions" here I need all the help I can get as I'm very adept at shooting myself in the foot as is.
I hope this helps or at least provides food for thought. I'll be watching your recovery from this little setback with great hopes!
Cheers,
Lance