My air-cooled overclock, should I raise voltage?

I've had many successful 6 hours sessions of Orthos Pri 9 and Memtest with this PC, but am continuing to tighten memory a little. I've gone up to 3.6 GHz, but the voltages scare me! How high should I go if I want this to last 10 years? Getting to 3600 Mhz seems to require quite high voltages like 1.375.

Any other advice would be appreciated since this is my first overclock!

E6600 2.4 GHz @ 400 FSB x 8 = 3.2 GHz (25% overclocked)
vCore 1.3125 (BIOS), ~1.24-1.26 (CPU-Z)
Temp 21 (idle) - 43C (Orthos Pri 9) using Thermaltake Big Typhoon. TAT slowly wanders between extremes of 43 and 46.

Asus P5B Deluxe, FSB 400
Northbridge is (400-333)/333 = 20% overclocked
Temp 25-27C

Memory - OCZ Platinum Rev2 Dual Channel 2 GB Kit rated DDR2-800 4-4-4-15 1.9-2.1V, 2.2 V also warrantied
vDIMM 2.0 (BIOS), running at DDR2-800, 4-4-4-12-5-35-10-10-10-10

ATI Radeon X1800 XL, core at 560 MHz (core 12% overclocked) memory at stock 500 MHz (can crash if changed up OR down, so I left alone)
Temp 35-46C (Rthdribl), using Zallman 9700-Cu cooler at ~30% fan speed

Also..
Using lowest voltages for FSB Termination (1.2V), NB (1.45 V), SB (1.5 V), ICH (1.025).
Disable Execute Bit - Enabled (i.e. protection on)
Static Read Control - Disable (doesn't seem to speed anything up anyway)
SuperPi 1M = 15 sec, 4M = 87 sec