BYPASSING A GAIN STAGE - QUERY

[NGW]

Hi Ultimate Tonesters,

I have had to shelve amp work for most of this year, due to other pressing issues, but I am now getting back into it.
The TUT Forum is looking a bit quiet; where are you all?

I have a query regarding bypassing a Gain Stage, which is a bit foreign to how I would arrange a Drive stage, so this is not something I have tried before.

The attached circuit shows a 4 stage preamp that uses 3 for Clean and adds the 2nd stage (V2B) for Drive.
The cct. is shown in Drive mode and when switched to Clean, Relay 1B enables a full bypass of the 2nd stage. 

In Clean mode; would you advise grounding the output from V2B, as shown with Relay 2, to remove any possible signal or noise from V2B entering the grid of V1B; or will the Clean Bypass be sufficient to ensure uncorrupted Clean sound?
Modifying the PCB traces and installing wiring to enable Relay 2 to ground V2B output is not a fun job but, if it is advisable, I will do it rather than have the clean sound compromised.
The owner loves the Clean sound and doesn't want to lose it.

Thanks for any advice,
Noel