I put my KJ2 into storage since the beginning of December last year.
Next week I'll be starting it.

Any "procedures" to do, or just turn the key and drive off (hopefully)?

If you are worried about starting it after 3 months take the lead off the coil and just turn it over for a minute or so so the oil gets up in the engine.
Then reattach the lead and start it without revving it just let it idle and get itself right until it's up to operating temp.

if your going to do that, better to unplug CAS car will crank but not start. cranking for a minute seams a bit excessive to me. because the parts are all moving anyway, whats the difference between that and starting the car? fuel does act like a lubricant a little bit, hence why i believe the advance magnas came with hardened value seals to be more compatible for LPG (someone correct me if im wrong)
id be more inclined to
*top up a few L of 98RON from a jerry can. (fuel does go off, and the RON drops as the volatiles evaporate away but 3 months shouldn't be a problem )
*check oil level/change if nearly due.
*check coolant level
*if battery is not maintenance free, top up with distilled water.
*let key sit in "on" position for a second to let fuel pump prime (if the magnas do that, most cars do)
*warm up to normal temp before driving

We have cars which have sat around a lot longer than 3 months, The procedure is to check the coolant (you can check oil but if it was full when you left it then it will not have evaporated), insert key, turn, start and let idle for a few mins.

Thanks guys, good to hear it should not cause issue.

I was primarily concerned about the hydraulic lifters being stuck or something?
A friend left his car for 2 weeks and after starting the lifters were very loud

Thanks guys, good to hear it should not cause issue.

I was primarily concerned about the hydraulic lifters being stuck or something?
A friend left his car for 2 weeks and after starting the lifters were very loud

Mine had noisy lifters after a week of sitting there. Saying that, it was nearly due for a oil change, some Mobil 1 and lifter free + tune up cleaner fixed it all up

I'd be very careful . . . . lift the bonnet and check for mouse and rat nests, millipede invasions, snakes, tarantulas, redbacks, kittens . . . look for chewed wires, rubber bits etc.

Found a mouse nest in my TS air cleaner, must have come in through the air intake. lol

Lifter noise: If the engine has stopped with one of the valves pushed down, the lifter would have leaked down and you will get some noise, but it should go away quickly. Your tyres might make some thumping noises where they flatspotted against the ground, should go away as the tyres warm up. They might need some air as well.

Might get some belt grumbles too.

And wash all that dust off the car! lol

Mine sat for 7 months, all I did was check coolant, oil, etc, started the car, let idle and drove.