toyota factory gps 08-10 scion?

[jgilk1]

Ok so i am cheap and don't want to spend $250-$400 on a nice in dash gps head unit i do know that scion still used double din head units till like 2010 and toyota is still using the 2 plug harness they have been using since the mid 80's

so getting power in and audio out is generally not a problem and neither is the gps antenna... as ther like $8 on ebay...

the question is has it been done and do you think installing the 08-10 scion head unit in a 92 4runner with out steering wheel controls might/will cause any issues?

oh for reference heres the back of the head unit in question

 

[broken wrench]

Should be fine without controls

 

[jgilk1]

Should be fine without controls

i didn't think they were and its not a secure link head unit like on most Mercedes where you have to go to the stealership and get them programmed...

so upon further investigation i have found this...

http://www.ebay.com/itm/TOYOTA-SCIO...t=Car_Audio_Video&hash=item4ad7693126&vxp=mtr

yes $150 to adapt the factory usb and aux port... (the bottom right is the gps antenna connection)

so $120 for the head unit and $150 for the usb... think i can do with out usb and 3.5mm input on initial install though i know a good location for them