[bigscore]

I'm in the same dilemma with my 540.

I ordered the 101mm tips from Ali Express to mount to my Remus catback using a G30-M5 diffuser and it did not fit properly. The 2 101mm were too big to fit properly.

Back to the drawing board i ordered both an 89mm tip and a 93mm tip to see which would fit best.

Fingers crossed!

Update.....

I had the "outer" edges of the quad diffuser on my G30 M5 style diffuser trimmed and it was ample enough to fit the outer tips (Quad exhaust).