When I traded in my '08 SERK Annie, both dealers I was trying to deal with said that they would give me the same for it modified or as showroom stock. I took my V&H Dresser duals off, V&H oval mufflers, SE AC, leather tour pak and traded. They allowed me $23k in on an '09 SERG the week before the '10s came out. I was holding out thinking they might do another SERG for '10, but when the SESG hit, I was all for getting one of the last '09 SERG's.
They had my bike for almost 9 months and sold it for $25k. I sold all the take off items for around $1,500. I consider that a pretty good deal.
Years ago I would try and sell before I would ever trade in, but in my older age, trading in is worth the stress of getting it advertised and dealing with private buyers. I would still sell locally if someone wanted to buy it, but I would not actively promote a sale.
I think the dealer could cut the adders off the top of the MSRP and that would probably be a pretty decent deal for you.
I agree with others that your bike is worth more than the trade in price, but there is a cost to the dealership to do the trade and if you push them they will probably cut the prep etc stuff off. I would ask him straight up if "stock" is worth the same as your bike is now. Also as someone else said, try another dealership and even if they don't have the same color you want, use their pricing, if better, to push your dealer down a bit.
Good luck with your purchase if you move forward.