VPI cartridge install f/phase inverting pre

No. Only one swap.

I've never seen or heard of a preamp with a built-in phono
stage, where ONLY the phono stage inverts phase? Usually
it's all or none, but maybe they do exist?

Jmcgrogan2...according to the SLP98 owner's manual, BOTH the
line and phono are inverting? I used to own this preamp
with phono and never recalled this difference. That's why I
looked at the manual.

From the manual, (page 11):

Amplifier – Speaker Connection

 The SLP 98 (line and phono) preamplifier is phase
inverting.

 This will require you to connect the positive
speaker terminal to the negative binding post
on your amplifier. The negative speaker terminal will
connect to the positive binding post
on your amplifier.

Dover...thanks for info. I did not know this. I was wondering how a line stage and phono stage in the same chassis, using the same power supply, could do this.