As per request, here is the second part....
So to get adrenaline working you need a PSP game/demo to convert/sacrifice to make the Adrenaline app. As far as i know any game/demo will do. Many people use the LocoRoco demo since its small so thats what i used. If you already have a demo or game to sacrifice then you're good to go. if not then you will need to use the spoofed PSN to log on and get yourself a game. Spoofing should already be enabled so all you have to do is make sure your account is activated in the settings, log in to the PSN store, grab your sacrificial PSP game off PSN and move to the next step.
Next is installing AdrenalineEasyInstaller VPK file which is what i used.
https://github.com/Freakler/vita-AdrenalineEasyInstaller/releases
and also you need an OFW file from SONY
https://www.playstation.com/en-us/support/system-updates/psp/
rename the Official Firmware file to 661.PBP
On your VITA create a folder in the ux0:/pspemu folder and name it "adrenaline". copy the firmware file in the "adrenaline" folder you just created.
Copy the AdrenalineEasyInstaller .VPK file to the VITA. As long as its in the ux0: folder im not sure it matters where it is but some people make a dedicated VPK folder for all these types of files and thats not a bad idea.
However you chose to do it, put the adrenaline installer on the Vita and install it the same way you installed the other vpk files.
You should now have an Easyinstaller app on your homepage now. Go ahead and boot that up.
It'll give you some prompts and preps like making sure you have the 661 file in the adrenaline folder and things like that. Surprisingly in my mod I actually missed a step and it didnt matter. The installer found whatever i missed, corrected it for me and proceeded automatically. Still to be on the safe side make sure you have everything where it needs to be.
Once thats done it'll autoboot to PSP mode. To exit from PSP mode back to VITA mode, hold the home button, go down to adrenaline settings and then select exit pspemu application.
Also now, whatever PSP software you chose to use for the installation is now permanently the adrenaline application. You will use that to access PSP emulation mode from now on. Thats pretty much it. The only thing left to do is add games and that's done the same way its always been done on a regular hacked PSP. Just hook the Vita to a computer via USB (vitashell) or FTP (molecule), Go to the ux0: > PSPemu > PSP folder and then inside there you have an ISO folder and a GAME folder. PSP ISO files go in the ISO folder and PS1 and emulators go in the GAME folder.
Sorry if there are any errors in this im doing it from mostly memory of a mod i did a couple of weeks ago. I did reference some pages and videos so hopefully its all accurate.
also here is a good video for reference
https://www.youtube.com/watch?v=SgiKDo3G3oE