Too many inputs?

I'm planning on running a AIM PDM32 as I've seen a few other MR2 owners running these on their personal road cars with good results, although I'm struggling to understand some things which i don't this the course was suited too.

For example, I want to use the OEM stalks and Buttons to configure things like my headlights, turn signals, wipers etc... But looking at the wiring diagrams is seems like id have a hard time getting these into the PDM, or is there a more simple way I'm not understanding?

Also, I've realized that there will not be enough outputs for absolutely everything so I'm going to try and use some of the stock wirings and then feed that back to the PDM. Obviously within the amp limits but I don't even know where to start as the diagrams don't really show a "power feed" wire for each individual fuse, my idea was to take lets say the 'Radio & CIG' remove the fuse and use the wiring that links into these systems to splice into and use an output on the PDM, therefore they'd get power and id lose the fuse and relay.

Here's some documentation - http://www.shinny.co.uk/toyota/MR2_SW_1993_ELECTRICALWIRINGDIAGRAMS/

Have you considered adding a the RIO02 Expansion? It adds 19 digital status inputs, and two Low-Side switched outputs.

https://www.aim-sportline.com/download/technical-sheets/aim_rio02_103.pdf

Nice, I'll have to get one on order but it still baffles me how people are running the stock setup with just a standalone AIM PDM32, unless the ECU can take some of these mechanical inputs?

Would my fuse method be the best way of splicing into the stock harness also?