Swapping bracelets - good or bad idea?

[Vicious49]

I have a P serial 16570 with SELs and a T serial 16700 with hollow end links and an flip lock clasp. I was planning on getting an SEL bracelet with oyster lock for my GMT anyways so now that I've decided to sell the 16570 I am thinking of swapping the bracelets. Then I will have the GMT with the bracelet I want without having to look for one on the secondary market.

1. Will I have an issue with the bracelet swap? I'm guessing no as long as I swap spring bars too, as they share the same case.

2. The much bigger question is does this affect the value of both watches as neither is all original any longer? In which case, is it better to keep them stock? I'm really more concerned about the GMT since that's the one I'm keeping.

3. Since I'm selling the polar, about how much of a monetary difference does this make? So I can price it appropriately.