Thanks Wokka,
The process itself is pretty simple (the blue guards/covers took me about 10mins to do all 3) after a bit of practice attempt on the the orange. The hard part was finding decent sized vinyl sticky sheets that weren't solid color only.
I finally found a few sheets as part of a set from a guy on ebay, who specialises in vinyl laptop covers.
It was just a matter of stenciling out the pvc shapes onto the Vinyl sheets and then applying it the same way as an auto decal. Lightly wet the pickguard with a misted on solution of water/detergent and lay it facedown on the sticky vinyl. This allows you to reposition a bit and remove bubbles before the Vinyl sticks firmly. Then once it had dried and adhered thoroughly I used a box-cutter knife to remove excess any vinyl that was overlapping the PVC.
And presto, left with unique and durable art thats pretty scratch resistant. I used the same stuff on my jeep bonnet and thats endured 2 years of sun, storms and anything else with little to no color fade of wear and tear