Are you running 13* base timing on pump gas? If so, you are asking for trouble with that much total timing at full boost (29*). Might be best if you are gonna run it without a tune to lock out the distributor at ~20-23* with 93 octane. It would be sluggish down low but should do you well at WOT.
EECTuning.org can give you all the info you want about tuning.
As far as plugs, you should be able to run an autolite 3923/24 depending on what thermostadt you are running. Rick91Gt has told me that NGK7173 will work better as they don't run as hot as the autolites. Gap on the plugs should be reduced to around .32-.35