How to increase MXR 117 Flanger volume?

[MAO]

Need some help.

There is a bit of a volume drop with this flanger.

I've read that you can increase R39 to increase volume. but this also increases the bass frequencies.

Instead of adjusting R39, would reducing R37 and R41 by an equal factor accomplish a volume increase without affecting the frequencies?

I'm hesitant in trying it without some advise as the pads on the board are old and brittle as I discovered the hard way. Don't want to take a chance in damaging the board unless it's a viable countermeasure for the volume loss.  

Thank you,
Mike