Printer Problem, I need Help

Network Description:

Old AS/400 connected via twinax to Twinax splitter block, from
Block 4 patch cables run to 2 Powerstar IV's ( transition Networks).
and from there run to 15 printers.

Problem:

Client has purchased a new AS/400 server, and wishes to have both
online at the same time. This we have done, BUT they wish to be able
to print to any Printer from Either Unit.

My background is in PC networking, I have little knowledge of the
AS/400.

1) is there a Print Switch that i can put between the two serrvers and
the twinax block?

2) can I print from the new server to the old one via the network and
have the old server feed to the printers?

3) is there a different possible option I have not considered?

Thanks in advance for you input.
Steve