A driver who has come through the system could answer better, but, an IMSA lites ride, Patron GT3, WC, etc.. with associating one self with teams that are running in GTC or LMPC would seem the best way. Intersport, GETG, AJR, TRG etc.. from the ALMS side. There is an ACO school for prototypes as well as various and sundry GT series and VdeV in Europe that would fit the bill. Then of course getting known by the teams in the LMS to further the possibilities of moving into a P-2 or GTE-AM in the Future.
And welcome to the forum 'simontibbett'.
L.P.