Timing belt change

[n17ikh]

Hi all,
I'm new to the forums and I thought I'd introduce myself by doing a big job:
It's about time for the timing belt change on my 01 Tundra and it's at 180K miles. I figured I'd do about everything under that cover while I'm there. So, I'd like my parts selection to be checked over by someone who's done this before:

    (96761-24019) O-Ring
    96761-35035 O-Ring
    (00295-00103) RTV
    Timing Belt 13568-59095 48.07
    Water Pump 16100-59275 $112.59
    Radiator Hose 16572-0F010 20.65
    Radiator Hose 16571-0F010 13.41 
    Thermostat 90916-03100 12.83
    Thermo Gasket 16346-50010 3.46
    (90916-A2003) serpentine belt
    Tensioner Assy, Tmng 13540-50030 45.78
    Tensioner Assy, Serp 16620-0W036 65.74
    Cam Seals 90311-38065 11.80
    Crank Seal 90311-43006 7.32
    13505-of010 idler sub assy $55.00
    13503-of010 idler sub assy $55.00

I found everything except the two idler sub assemblies. The part numbers are mostly valid except for a few things that have been superceded - Annoyingly, the parts sites I found don't show the part numbers of the items in your cart. I did go into the illustration though and found the two parts most likely to be the idlers:

Mechanical Catalog - 2001 - Toyota - Tundra
Engine, Camshaft and timing, Tensioner pulley, Tensioner pulley, tundra, sequoia, left - 4.7l - 2000-04 - 4.7L - 2000-04

and

Mechanical Catalog - 2001 - Toyota - Tundra
Engine, Camshaft and timing, Tensioner pulley, Tensioner pulley, tundra, sequoia, right - 4.7l - 2000-04 - 4.7L - 2000-04

These parts are both $66. I'm fairly sure it's the idlers.
So, how difficult is this job for a shade-tree mechanic who changes his own oil and rotates his tires (but nothing really ever harder than that) to do? Can I do it, or do I need to pay the stealership $900? This is $530 in parts (expensive job to screw up), the prices shown are old and probably wrong, from other peoples' postings. I figured I'd need four cam seals - anything else I need multiples of? Did I catch everything? I've got the Haynes manual. Anything I should know, do I need special tools other than a good set of wrenches and maybe a crank pulley puller?

Thanks in advance
-n17ikh