Hey Bro,
heres the 411, haha.
as for venetians, when i searched high and low a few years back there was not a usable template on the books.
Obrien Autoshades, here in adelaide offered to measure mine up and then have a template to make them, back then i was quoted $450, measured, made, both rear sides and tailgate.
i didnt have that sort of money at the time so i had to pass.
since then, MAYBE they have been measured and a template made ?
no drilling required with venetians, they locate in the seals and hold tight.
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as for your headunit.
as i have and alot of guys on here, put it in your glovebox.
no drilling, no cutting plus when the glove box is closed you can't see it, sneaky :)
i have a set of 6x9s in boxes sitting in my cargo area, again no drilling, screws, cutting.
with my amp neatly tucked under drivers seat, no one even thinks twice about a stereo :)
goodluck with it all champ, youve got a good thing there.
cheers, scott