Welcome
I don't have a lot more to say that Viffer93 hasn't, think he pretty much covered it. The TBR headers are really nice, be prepared to spend $300 for it though (and I'd go for the left exit). As Veefer said the 4th gen (94-97) headers and collector will work and will be much cheaper.
14.5V sounds a little high, but it's probably fine. I'd replace the R/R while you're thinking about it, I spliced in a SV650 unit to mine, you can find them for less than $20 and keep your current one as a spare. Plus check all the connectors, they seem to burn out.
If you're going for an undertail exhaust, you might want to replace the subframe with one that already has the exhaust there. Some have put the 6th gen (02-09) tail on their 4th gens (pioneered by Fotomoto), not sure how it will work with a 3rd gen though.
Looks like a great project