I've finally finished replacing the stock V7/V8 pickups on my RG2020x with a Duncan Jazz (neck) and a Duncan Custom Custom (bridge).
I'm putting up this field report post mainly to help future Ibanez players who want to swap the pickups with Duncans. This is especially for dual humbucker (H-H) configuration owners that have a 5 way switching through a VLX91 switch.
First, check the polarity of the Duncan neck pickup's inner coil. It should attract the Duncan bridge pickup's outer coil, so as to deliver hum cancelling in position 2 (neck inner coil in parallel with bridge inner coil). If the two coils attract, you're business. If not, flip the magnet of the neck pickup. Loosen the base plate of the pickup a little, slowly remove the protective tape, and nudge out the magnet. Once it's out, rotate the magnet 180 degrees and reinsert it. Now, the 2 inner coils of the neck and bridge should attract.
Now, the wiring codes.
V7 has the following wire color codes:
North coil -> Start: Black, End: Red
South coil -> Start: Green, End: White
V8 has the following wire color codes:
Red: Hot, White: coil split wire, Bare: Ground
Once that is established, we can easily map the V7/V8 to Duncan wire colors as follows:
On the V7,
Black = Duncan Black
Red = Duncan White
Green = Duncan Green
White = Duncan Red
On the V8,
Red = Duncan Black
White = Duncan Red and White shorted
Bare = Duncan Green and bare shorted
Now, the VLX91.
At this point, I'd like to extend a HUGE thanks to Scott for providing this link that demystified the 4-pole 5-way VLX91 switch: http://www.his.com/~sha3u/gear/vlx91.jpg
The VLX91 has four poles, hence the four set of lugs. Each pole has 6 lugs, with the common lug being the lowest lug (numbered as 0). Scott's diagram explains how the other lugs are numbered.
Once the switch and wire codes are figured out, you can heat up the soldering iron and get down to business.
Now some report on the TONES. The Duncan Custom Custom really delivers the Van Halen tone is spades!! Very deep mids, sweet highs, and decent bass. I got mine barely about $40 used, definitely beats spending $160 for Duncan's EVH custom shop model. The Jazz is a total misnomer. It's a match made in heaven for shredders and metal players! Very articulate, and a total joy to do 2-hand tappings. Do keep in mind that my guitar is a mahogany bodied RG2020x. I'm not sure how they'll perform on basswood guitars though.
Before I end this report, some advice on pickup mounters (for direct mount guitars). Some folks, including me, dislike the rubber piece that mounts the pickups. Largely because they go out of shape after being pressed down for quite some time. I used multiple plys of basswood strips glued them together, and used them as spacers. Works like a charm.
That's all folks! I hope with this, you'll find future pickup swaps a breeze.