Also, I ended up putting a lower gain tube in my Slampegg and now I have more control over the usable range of the input gain.
Aha! Bingo! I switched out the 12AT7 with a 12AU7 and turned the gain down to 9 o'clock on the Slampegg (right before the D strings starts distorting), ditched the HPF PRE and the Redeye and we're cooking with gas now.
I can appreciate not having to run through 4 different preamps to get the tone useable with this pup - we're friends now.
Thanks for your help, gang.