Don't know about the color dyeing part however in 2004 Sunlines, Our T2499 and the T310SR, the vinyl stops about 6" or so under the carpet. Must of been a cost savings thing. Floor plan and how much carpet you have may also dictate how much vinyl is there or not.
And like Jim said, the zillion staples. On ours, Sunline folded the carpet to make the edge seam to the vinyl. Meaning they turned the carpet fiber side down on the vinyl, stapled it a zillion times and then folded it back up and ran the rest of the carpet to the wall etc. While I am joking on the zillion, odds of having about 100 little staple holes in a 6 foot run is not that far off.
Good luck and let us know how this comes out.
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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