Here's Maniac Mechanic in the Sub Craft  
Here's Maniac Mechanic in new footage in Angel Grove
Once you see footage of Maniac Mechanic inside his vehicle then it's the start of Sentai footage. It then cuts back to new footage of the Yellow and Green Rangers and then once you see the Yellow Turbo Cart then it's back to Sentai footage.
Once it cuts back to Green Ranger then it's back to new footage and then once it cuts back to the footage with the Turbo Cart in it then it's back to Sentai footage.
This shot of the Yellow Ranger is when it goes back to new footage.
Here's new footage of 3 Rangers and Storm Blaster
Once you see Maniac Mechanic again then it's back to Sentai footage.
Any shots you see of the Lightning Cruiser taking on the blasts from Maniac Mechanic's vehicle as well as its steam/smoke/mist attack is new footage while the Maniac vehicle is firing its moves off in Sentai footage.
The shot of Storm Blaster taking on the blast from the Maniac Car's last weapon is new footage so while the Maniac Car is firing the wheel move or whatever they are in Sentai footage, the Storm Blaster is taking the blast in new footage.
The footage of the broken down Storm Blaster is Sentai footage, they just cleverly edit around it to show only the Blue and Green Rangers due to Yellow being untransformed in Sentai footage.
Any shots of the Rangers working on the broken down Storm Blaster is new footage.
After Yellow tells Blue and Green that it's okay to leave to help out T.J, it then cuts to Sentai footage of Lightning Cruiser.
Once you see the Storm Blaster make it to the site where the Rangers and Maniac Mechanic are at then that's the start of Sentai footage for it.
All Giant footage is Sentai footage.

Sentai footage comes from Car 44