New query but related to similar threads on too much heat

1978 Corvette Pace Car. Had aircon which has now been removed, at least some of it  Compressor and condensor in front of radiator and most of the under bonnet (hood) gubbins has gone.  I think most of the bits are still in the passenger compartment.

As per other people on similar threads I have the problem of too much heat coming into the cabin. Originally the heater wasn't turning off as the control was broken but I have replaced this and this now blows cold air.  

I get waves of hot air while driving, but not while stationary.  I have extra vents in the footwell which I assume were part of the aircon but as it is not possible to drive with my head and hands in the footwell I can't tell if the hot air is coming through these or just the heat coming through the bulkhead and floor as described elsewhere.  

I can see what look like vacuum actuators in the passenger footwell but can't tell if this should be opening/closing a vent, or if it is working.

A few basic questions to start with.  

1) If I just block up these vents is this likely to help?  

2) Is it likely to cause me any problems?

3) If the actuator in the passenger footwell was part of the aircon which i have no intention of re-installing - is it ok to remove it?