Forget that.
High Power Chambering. That would either be a change from 8P(f) +5 AP to 8P -1 AP or 8P(f) +5 AP to 10P +4 AP, depending on how you see the HPC mod working.
But the total amount of RC you can fit into the Viper, is 3. Weight, personal grip and a stock. It's no marksman's weapon. A FA mod would be usefull for suppression only.
As to Zilfer's question about Recoil when firing with guns in each hand, RC penalties and RC compensation only matter for each individual weapon.
So, if you fired a narrow burst with your right hand, and had 2 points of RC in that gun, then that shot would be fully compensated. If in your next action, you shot with a second gun which also had 2 points of RC, then that shot would also be fully compensated.
If you fired both guns at once, and had no RC, then you would split your dice pools as you choose and apply the individual RC modifiers to each DP separately.