After much reading I have always used Luberfiner PH832, mine is 2wd, filter is 8" tall. Normal shorty PH1218.
http://productguide.luber-finer.com/Home/PartDetail?partNo=PH832
All filters for vehicle, mines a 1995 but you can change the year...
Liquid cooled alternators work well even if sinking them, some fab work needed of course.
http://www.bosch.co.nz/car_parts/en/downloads/Liquid_Cooled_Alt_Broch.pdf
http://www.ebay.com/itm/2001-2003-BMW-X5-4-4L-E53-OEM-LIQUID-WATER-COOLED-ALTERNATOR-GENERATOR-/321989883158
Phillips/Temro block and circulating heaters used for our generators 24/7, last about 3 to 5 years. They are kept at 130f, on mains failure units have to start/go to 1800rpm and transfers to full load in under 3 seconds.
I use jacketed 4awg fine strand cable, soldered lugs, conductive grease (for dissimilar metals contact) then spray with undercoat oil. Leave a service loop for flexing.
dielectric grease will help with the corrosion part (but a dielectric resists electrical flow) what you should use is electrical contact grease.
http://www.plews-edelmann.com/electrical-contact-grease-/-2-oz-tube/
I went with the big rig plug (unplugs easily) and a HD 3 receptacle cord connected & treated to it. Block heaters/oil pan heater/batteries maintainer so I can pick & choose and when it sits for many days only the maintainer.
I know 2 that tried different products, 1 began flaking in a few months & the other less than 6 on off road rigs not daily drivers. Don't remember the products used. One went to the tape wrap & the other had professionally done & no problems since.
Great job on the header some production pieces I've seen aren't that good. Have you considered professional ceramic coating or wrap over painting it to keep more heat to the turbo.
Make good grounds that don't corrode. The low ohms tester I use goes to 0.000 ohms, I look for 0.250 or better. And yes all the ones jrsavoie added aswell.
Always hearing about bad grounds, redid mine +8 years ago because of issues (broken braided straps) and no problems since. Up here in the rust belt with salt & brine being put down on the roads in winter it takes its toll.
Added 2awg fine strand wires for flexibility with crimped & soldered...
Sorry no pictures. The grounds are where it is easy to get to & check. eg. from batteries straight down to frame rail, drill & tap.
For induced noise I've used ferrite cores for power cables, RF or sensitive signals will or should be shielded.