Most of the interior shots of the Skull Cavern comes from Episode 2 and obviously any time you see Vypta in the same shot as the other demons, it's Sentai footage. In this episode, she's only in new footage if she's the only 1 in the shot.
This shot of Vypra however is new footage despite seeing Jinxer's hands in it
This next shot is more than likely recycled footage from Megaranger.
Yes, this next shot is also a recycled shot from Megaranger.
A shot of a tornado as shown on the Aquabase Monitor is Sentai footage.
This appears to be new footage
As soon as you see the morphed Rangers it's new footage.
It looks like the shot of Diabolico talking to GoGoV in GoGoV Episode 2 is the same clip that's used for his talk with the morphed Rangers however it looks like it's been edited into the footage since the water surroundings don't match with the footage.
The effect that causes Diabolico's communication channel to disappear is redone for the Lightspeed episode.
After Diabolico's communication channel closes, the tornado returns in what I'm kinda sure is new footage. Any shots of the tornado attacking something (other than the Rangers and their zords) is definitely new footage though.
Currently all footage of the Rangers is in new footage.
This shot is when it goes back into Sentai footage.
I'm not sure where the shot comes from where Red takes out his Blaster, aims it and then fires it before we see it cut to the next scene of the Blaster's beam going towards the tornado.
All Whirlin' footage is Sentai. All Batlings stuff is Sentai.
Here's new footage of the 5 Rangers All following shot of the Rangers which includes the Yellow Ranger calling for the zords is new footage.
Once you see the zords, it's back to Sentai footage.
This shot of the Rangers is indeed Sentai footage.
They kept the same altitude readouts for the Shuttle but it looks like they just redid the background color and it's also possible they changed the "Unstable" readout but after checking it again, I'm not so sure.
This is new footage however once you see the opened compartment of the Med Rescue 5, it's back to Sentai footage once again.
All footage of the cars is new footage however if you see them in the same shot as the Med Rescue 5 then it's Sentai footage.

Following info comes from GoGoV Episode 2.
Here's an exterior shot of Skull Cavern.
Here's Diabolico
Here's Jinxer and Loki
Here's Sentai Vypra and baby Impus
Here's a shot of Diabolico's Card, this is the card that he gives to Jinxer so Jinxer can call forth Whirlin'
Here's Whirlin'  
Here's the 5 Rangers.
Here's a shot of Red with his Blaster.
Here's Whirlin' once again.
Here are Batlings, the first Sentai foot soldiers that were kept in "Power Rangers" as the main foot soldiers since Zeo kept the Cogs from Ohranger.
Here's a shot of the 5 Rangers with their Batons.
Here's the Rescuebird once again.
Here's the Unilaser.
The Unilaser destroys Whirlin' Here's a shot of the Robot activating the Supertrain and here's a shot of the Robot in the Supertrain cockpit.
Here's Jinxer's Card, he uses this Card in order to resurrect and enlarge Whirlin'
Here's the Haz Rescue 4.
Here's Giant Whirlin'
Here's the Lightspeed Megazord Saber.  
Here's a shot of Matoi, he's the one who transforms into GoGoRed or whatever Red's name is in GoGoV.