I'm currently in the build of a 3inch twin system for my 32R, I got custom mufflers being built. Than I'll fab the rest of system myself. Which will be twin 3inch into a 4inch merge just before the diff.
The reason why I'm going twin 3 is because I want max ground clearance, I can run good free flowing mufflers to it is quite, and at the same time it flows heaaaaps. So my exhaust will not be a restriction what so ever with my -5s, the exhaust is the one of the main things that smuthers them.
I'll post pics once it's all complete, it prob won't be done for another month as I work FIFO so it will have to wait till I'm home again to continue on with them.
Once they done, I was thinking of building a jig for the system, and making up 4-5 of them and selling them in a GB but that won't be for awhile, it will need to be built, fitted and some dyno work done to ensure it works.
Cheers
Deano