HP cartridges and pigment-based inks

Hi all. I'm using a Deskjet 9800 for larger (13x19) prints. I want to be
able to print on archival fine art paper with pigments, for quality as well
as longevity. I know the HP #96 cart uses pigmented ink. What I would like
to do is refill some used color carts I have (#97 & #99) with carbon inks
for hextone printing.

My questions a

1. can quality pigmented inks be used in the #97 and #99 carts?
2. what is the best way to flush any remaining ink from the old carts?
3. will I have to reset the printhead chips after refilling, and if so, what
is the best way?

Most printing forums support Epson printers, so I have been able to find
little information on HP products.
My alternative is to purchase an Epson 1280 and configure for continuous
flow hextone printing. I'd rather not spend an extra $500 when the 9800 is a
perfectly good printer.

Thanks,

Sonrise