While the head is willing, the body is another matter. Smith has had some issues with his shoulders and had surgery on one of them.
"I know I'm going to struggle this weekend, as I had a shoulder replaced 12 weeks ago. The other shoulder has damaged ligaments, so I'm going to find it hard.
"I know I'm pushing my luck a bit, but I can't miss out on this opportunity. The car body work is great, mine not so much these days. We'll be all right, though, and being around all these young drivers keeps me young."
The FT-60 single seater used in the TRS is a far cry from the single seaters Smith used to race and from the F5000 he regularly races today.
Younger drivers are familiar with the look and feel of the FT-60, as it is an FIA-accredited race car with the same chassis used in international junior formula championships.
"The cars are so different these days, and with the halo, the steering wheel is in the wrong place. It causes your hands to point skyward.
"There are other differences [to F5000] and the ride is quite hard, but hey, that's what's been built and everyone's got to drive them."
The TRS has evolved into a series dominated by international drivers but this weekend, the field is full of New Zealanders, young and old. On the grid are Shane van Gisbergen, Andre Heimgartner, former winner Daniel Gaunt, Porsche Carrera Cup winner Chris van der Drift and another former NZGP winner and Supercars great Greg Murphy.
"It's awesome having Andre, Shane and Chris racing, and obviously for Kenny and his 50th Grand Prix, it deserves to be recognised and honoured," Murphy said.
"It's just an incredible milestone and is probably a world first for an FIA-sanctioned Grand Prix — one of only two GPs helps outside F1."
Murphy has been away from regular competitive racing for a few years and is looking forward to tomorrow's challenge.
"It's been a very long time since I was racing full-time; 2014 was the last year. I've done a bit of GT racing since then and a few other things, but nothing that'll make me fit for driving a single seater.
"I really love these type of cars, as it's all about the driving rather than letting a whole heap of aids help you out — it's all about feeling the car and what it's doing underneath you.
"I'll be a little bit off the mark, as it'll take me a while to get the brain switched back on for these type of cars. I can drive them, of course, but getting the best out of one is the trick.
"The body will take a bit of a hammering as well and by the time I role around for the Grand Prix I'll be feeling it for sure," said Murphy.