no high pressure rv2 help!

1972 dodge demon 340/ yes factory 100% stock a/c . yes on reading the manual . proper oil non parafin. 8-10oz of compressor oil. never ran the system prior resto on the car. In Chicago heated garage 70 degrees farenhiet. 25 degrees inside car with temo gauge probe in vents. No on blocking condensor to raise pressure. Per the mopar book on amount of r-12. The freon is from the 70s good stuff.Afer installing proper amount of freon . I added more to see if situation improve - no change. Original factory condensor cleaned out prior installing . The only thing I havent changed is the expansion valve, After shutting down the presures eqalize 70lbs on high 70lbs on low.?????????????????? Guys if I jump the temperature sending switch on the inside clutch remain on constant / low side drops to 15 temp inside vent 25 degrees almost snows inside / only 50lbs high side . Obviously cant leave that way freezing up