Alarm / immobiliser / tracker???

Hi all, 

I'm in the middle of getting my MK1 finally put back together after a rather long rebuild and want to see if anyone has fitted any form
Of tracker / immobiliser device as I figured while the interior of the car is gutted, maybe it's a good time to fit something?

Any ideas are all appreciated 

Tracker, Apple Air tag glued to the frame

Imobilizer, just remove the Fuel pump relay.

I fitted a basic Cobra Immobiliser, the fob type, when I had the car all stripped out, pretty straightforward. It does 2 circuits so I did fuel pump and starter. I removed the blanking plate on the dash where the choke handle would be on carb cars and the contact point for the immobiliser fitted in the hole with no need to hack the dash up.