Fitting Givi luggage when no bike specific kit exists

[talkToTheHat]

I have an old XV535. We go everywhere together, supermarket, diy store, whatever road trip I'm doing next.

I currently have a renntec sissy bar + rack with an E250 monokey plate holding a cavernous E45 topbox on. I seem to live out of this and 70% of the time it's fine. Cargo net and bungees sort out my impulse purchases of big items. Long trips or serious shopping currently require panniers. I had leather ones thrown in with a GZ a while back and they were quite waterproof, at least they'd be guaranteed to hold onto at least an inch depth of water inside if it rained. I got some cameron rolltops about a year ago, they're really waterproof, but they are a pain in the ass to mount, and can be quite bouncy unless one goes to town on the bungee bondage. And I broke them.

I want some more monokey luggage. Could live with E21s and no top day to day, and a pair of E36s and the existing E45 or even going all E45 would sort my caravanning needs out.

Givi don't make anything bike specific for the 535.

Hepco and Backer make a nice frame, I suspect it is as strong as a very strong thing. https://www.hepco-and-becker-luggage.co.uk/library/pdfs/6504570002.pdf

I am considering trying one of those and two more E250 plates, but I'm not sure the E250 plates are a bad idea. Has anyone tried this?

At worst I can probably get some plates welded to it and bolt on the SW Motech Givi adapters, I have a friend who is probably capable of that.

I'm also aware the wingrack has a universal fitting kit. Y127 Has anybody tried this? Is it any good or is it flimsy as all hell. I'm a little concerned as the rack will have to sit quite far behind the available mounting points. I don't mind dong a little DIY if this is a good place to start from.