I think the consenses from majority of the owners is too toss it. I did the same. I made the decision to drop it after I lost one of 4 bolts that held it in place. I 4200'd all the bolts back in place after I removed it.

It was a tough decision because I personally love the old school rectangle exhaught tips on the SR1's as well as the oval tips on the newer fastechs. But it's just dead weight, plus I noticed immediately that the rattles disappeared.

So take the stock V flappers out and add the rubber ones on the outside?

NO! don't cut the wieghted ones out! that's your primary reversion defense.

just add the external flapper on the stock short, raw tips.

you will want to change to a nicely finished tip eventually or some bolt on/integral Corsas.
regardless have fun getting the stock ones out!
they are in there with 5200!