Greetings from Olympic Penn.
 

Owner of a FM Habu. 2007 PHRT with an ls376/480 conversion. Spent the last 10 mos getting break-in miles (doesn't do well in snow or heavy rain). Looking to some autox or track time. Ran afoul of the SCCA track nite in America folks when I tried to register last fall. Upshot was v8 powered roadsters (all makers) need hard tops or roll hoops which the mfger certified ( not Mazda) for rollover protection or an SCCA roll cage. Still trying to sort it out. My local track, Ridge MotorSports Track, sided with the SCCA. Have had to borrow/piggyback a track car for the last 6 mos.

The Habu is a great ride.

Welcome. Post some pictures!

Are you saying that the Miata factory top would not pass?

I don't know about the pass on the top. It did not work for me. Some other venues/ sponsors indicates (several years ago) that even with a top bolted on they still required a bar or cage for converts for hpde days is needed. My take away is that I should contact the track and sponsor and ask before showing up. I do have a plan of action. A hard dog transformer bar. It has both a "low" bar which works with the PHRT, and a high bar which is high enough to pass the broom stick check from the bar top to a structural point up front like the cowl base or body near the shock tower. It is supposed to pass almost all venues/sponsors (BMWCC being one exception). It does require a deck lid with holes cut to accommodate the 2 rear braces. Carbon Miata has lids in glass, carbon and carbon/Kevlar at reasonable prices that fit the PHRT.
Norm