Wha?
Not pick on Parker day but like on any old bike for instance I've had, I always considered it "restore" not "mod" to put an old one back together, it doesn't have to be bone stock, that would be more concours.
I restored a 1960 Matchless G80TCS, rare bike, 600 single, Typhoon Competition Scrambler that had actually been owned and somewhat heavily modded by Evel Knievel and sitting for 17 years... and although it wasn't Concours when I finished it, it was "restored" and I put so many amazing miles on that bike, maybe the best memories of any bike. A 65 BSA C15 would be second. I also restored a Norton, Triumph, Bultacos, a 1956 HD Panhead - in the living room for two years - and later several old Dodge trucks, two rare Power Wagons, and later still old farm equipment, sickle bar mowers.
So you can "restore" things your own way. I never got to see the guitar, that's what I get for having breakfast, so I can't pass my own harsh judgement on it ;]