97 lexus sc300, nav, confusing, how to wire this?

Alright so after searching a few pages on this I realized that the SC300 is a PIA to install a new HeadUnit in and keep the stock sub working lol. Now the questions I'm about to ask I know have been brought up and answered before but honestly I think it would be easier if it was in one area, so I decided to ask them again. I have both Metra Harnesses on hand 70-1761 and 70-8112, but after reading all kinds of posts I'm honestly not sure how to hook this damn thing up lol..........now I'm not a pro by any means, but I have done installs like this before on other cars without any issues but the SC is giving me a headache. I have a 97 SC300 with the stock Pioneer system (tape deck, cd changer) I want to install a Pioneer AVICF700BT and keep the use of the stock sub and amp (if necessary I will go aftermarket with the amp and sub, which ever is easier). After reading a few posts it seems as if the best way to install an aftermarket headunit is to hardwire and not use the hardnesses. I was looking at the pinout schematic found here [url]http://www.intellexual.net/faq/lexusstereo.swf[/url], but honestly I'm not sure about a few of the connections. The Pioneer has the following wires: Power Harness White: + Front Speaker WHITE/ Black: - Front Speaker Gray: +Front Speaker Gray/Black: - Front Speaker Green: + Rear Left Speaker GREEN/ Black: - Rear Left Speaker Violet: + Rear Right Speaker Violet/Black: - Rear Right Speaker+ Yellow: +Battery Red: 12V On/Off ORANGE / White: Lighting Switch Terminal Black: Ground Light Green: Parking Brake Blue: Antenna Control Violet/White: Reverse Gear Signal Input RCA Harness Front Output Sub Output Rear Output Rear View Camera In Video Input Audio Input ^^^^all the above are RCA Now on the same RCA harness there are the following bare wires: Blue/White: System Remote Control Yellow/Black: Mute I understand what all the wires on the Pioneer harness are I'm just not sure which vehicle harnesses to tap and what goes where. From looking at the diagram I would figure that the only harnesses I should be concerned with are A) Output to amps and light control D) Subwoofer OutPut and Mute Functions Am I correct in this or should I be concerned with plugs B and C? I know this is getting REALLY long and I'm sorry I just want to make sure that I'm doing this right. The way I understand it I would hook it up as follows: Yellow (battery) hooks to A1 (Amp 12V) ORANGE / White (ill) hooks to A2 (ill + to light control rheostat) Red (12V On/Off) Hooks to A3 (Acc, 12V Remote On) Black (ground)   Hooks to Chassis Pink (Speed Signal Input) Hooks to NOTHING, not used Light Green (Parking brake) Hooks to ????? (+ and ground of PB?) Blue (Antenna control) hooks to antenna Violet/White (ReverseGear Signal Input) hooks to my camera. That is as far as I have gone, could someone help me out and tell me if I'm going in the right direction...............or am I a complete moron lol....I will go with the latter lol. So i guess my questions are as follows: 1. Am I going in the right direction? 2. If I hard wire do I still need the 70-8112? Any help is greatly appreciated and I'm sorry for how long this turned out.

Oh I forgot the year is 1997 Lexus Sc300