msendit is offering excellent advice, and it's more current with specifics than mine would be.
The idea of dropping down a class is always one worth exploring. The TT guys are
all about winning, and if that will help you win then it's something to consider.
In that vein, "But he posed the question as to whether or not I thought it could be competitive"...could be a message in there. Might be worth asking before you get serious.
For reference, below are the TT4 & TT5 results from NASA NE's last two outings to the Glen. Looks like no one ran TT5 this past weekend. If it was me, first thing I'd do is take a look at the car models and mods those guys up front are running. I believe you can look at other NASA drivers' classification sheets online now, so most or all of what those cars are about is available to you. That would be very useful information.
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