As long as the RPM (LLT Copy) exhaust is the same width to the natural exhaust aperature, then it will fit this and should look great. I had to lower my exhaust down by cutting off the hangers and rewelding it.. was a little too high... Hoping not to have to do this as my stainless welding is not as good as mild steel, which is quite forgiving....
Well, for the small amount of money, its a good product and well built. My old man (owned a big boat building company in Sydney, in the day, said that it was a well made product - but the molds they used must flex a little making them a less-than-perfect fit...) but with a bit of ingenuity or hours of labouring beforehand it can look OK!
Aspired, it bridges both.. due to a small gap (imperfect fit from the mold). I used Sikaflex (you'll be calling it Stickaflex if you get it on your hands!) from underneath to dampen vibration and adhere the lot together...
I am guessing no, due to the flowing shape where it exits the barrel exhaust holes... plus, you would need to afix them with screws which may look untidy.
Once the second exhaust is filling the aperature, it will be very unnoticable.