I have the porportion valve under the master cylinder will that work or should I use an adjuster still ?
The one one with the M/C should suffice,Wilwood and others do a screw down type
proportioning valve for around $45 you could add in the line to the rears for fine tuning if you feel the need.
I'll be honest I don't have either in my Corvette style M/C set up I got from Master Power Brakes and have had no major issues in any panic braking situations so far.