Thanks for the thoughts guys. I guessed that the SP1 & SP2 undertails would probably be different, as after all the seat frames are different too and the ECU on the SP2 mounts in a recess.
kwtoxman - your pictures on your thread aren't working, buddy.
It may be Carlos ends up making an undertail only for an SP2 at first. Later that could be changed to fit SP1. Unless someone wants to send us an SP1 undertail to work out the differences and see if they can be integrated into one design?
Duckhunter thanks for the offer. I'm sure Carlos will read this thread, but I don't think he wants to make a mold from a soft shell, as that will tend to lead to deforming / wavyness in the finished product.
Was thinking today, it may be a good idea to include a rubber edge trim around the carbon, otherwise from vibration it'll scratch against the tailpiece's plastic over time.
There's lots to think about. Will use mine as a model and see where improvements can be made before he makes his design I think.
Meanwhile, my RC51 is now unridable, but no pain - no gain as they say.
Euro RC51 SP2: HRC WSB Ti Hi-Level, T1 Airbox & Snorkel, PCIII, Dymag CA5 Carbon Wheels, Ti64 Spindles (F, R & Swing Arm), Mori Link, Maxton GP7 Shock & Ohlins 832 Forks, Brembo GP Calipers & SBK narrow track (F), Braketech Disc (R), Brembo billet Underslung x 2 Brembo RCS, Tyga Triple, 7075 Stem, Probolt Titanium all over, Babyface rearsets, MR Complete Carbon Lineup, Custom Undertail & CBR 1000 LED, Watsen LED Indicators, Harris Brace, Giles clip-ons, Corbin seat, etc. 2013 BOTY.