"Testing before these races went well [last week where he was fastest in the morning] and we have the car working well.
"It's the first time I will have been to Monza this year and the good thing is that the team has been racing here for many years. They have the experience and I have full trust in them.
"I will be approaching this weekend exactly as I have in the past and not worrying about the championship points.
"There is this ridiculous rule in the Italian championship that you have to drop five races [out of 21]. I know I'm leading the championship but not by how much. All I know is that I'll be trying win all the races."
Winning the championship will do the Prema Power Team racer no end of good and will vindicate the faith the Ferrari Drivers Academy bosses had when they took the Kiwi on board in 2017.
With the healthy lead he has, and despite the oddness of having to drop five races, Armstrong is odds-on to walk away with the trophy barring a crash or mechanical misfortune.
However, he does feel any success will be tinged by what happened in Germany two weeks ago. Armstrong has this season been contesting two national championships; the Italian F4 of course, and the German ADAC Formula 4 championship.
He was also leading that series heading into the last round, albeit by a mere 1.5 points, but it wasn't to be.
"That was quite a painful loss as you can imagine [he finished second]. Winning the series this weekend will be great, but to be honest I don't think it will make up for the loss of the German championship. It was so close and it was a technicality that ruled us out.
"I don't know if you know, but the fire extinguisher went off in qualifying and that's why we couldn't fight for the championship win.
"Winning this weekend may not heal the pain from losing in last championship," he said.
The season-ending round is at the legendary Monza track that has seen some of the best races in Formula One history. It's a track Armstrong has raced on before and he's looking forward to sealing the 2017 championship at a place soaked in history.
"Monza is a fantastic place to race. It's a little bit big for Formula 4 and as it's not the fastest car [F4] it's going to be all about slip-streaming. It's not the best way when it comes to setting the fastest lap, but it is quite cool.
"My favourite part of the track are the high-speed corners like the Curve di Lesmo," said Armstrong.
The young Kiwi wouldn't let on what his plans are for next year but he did mention that straight after this weekend's racing he's off testing. In what we don't know yet, however an announcement is due soon.
Italian F4 points
1. Marcus Armstrong267
2. Job van Uitert214
3. Lorenzo Colombo187
4. Sebastian Fernandez181
5. Leonardo Lorandi161