MIDI volume/output gain range pedal problem

Hi, I’m trying to assign a midi volume foot controller via my AXE I/O midi in to control the output gain from my Mesa Boogie Mark 2C + Suite plugin. The range is -24dB to +24dB but it sweeps the entire range, I need to set it from -24dB to 0dB but cannot see which CC would do this with specified settings. I have tried the CC Value but I cannot see an option to specify a range. If anyone can help that’ll be great.
Meanwhile, I appreciate any advice.
Thanks.