Thanks John, I think I can carefully re-use the old fittings and put them on the NOS FV600 conduits that I bought back in 2015. These seem to be a compression fitting similar to a hydraulic hose, so I've managed to free them by cutting off the old sleeves. I'm still not sure how to replace the sleeves but I'll probably try gluing the fittings on and using heatshrink to tidy up the outsides. Once painted the replacements will be undetectable. I need to do all the front and rear sidelight/indicator conduits as they have been comprehensively mangled.
I'm currently looking to see where I put the old conduit with the 804-1058 so will get back to you on that if I may?
What bemuses me though, is that bearing in mind the number of these conduits present on old MVs, am I really the first person to address the issue?
Andy