10" drum or Kelsey-Hayes

I have a small block v-8 68 barracuda, with manual 10" drums all around. Problem is it pulls to one side. When you first start driving it the brake will lock up. By the time I turn around and go home it gets better but still pulls to the left. I have replaced the 3 rubber lines, blead the brakes, wheel cylinders seem to move ok, adjusted the brakes too. I had the drums checked, they dont need to be turned.

Checked the front end, no loose parts. Ball joints and tie rods are original, the car has 65K on it.

On my parts shelf is a set of spindals, dust plates, and core kelsey hayes 4 piston calipers. I pulled the caliper apart in an attempt to rebuild them but I'm having a problem getting them back together...and this is the first time I've done them.

I prefer to go with disc as the last time i got to the end of the track, the brakes were getting a little soft.

The car was also converted to silicone 20 years ago.

auto zone has loaded calipers for $110 each. RC4176 and 4175. I still need ball joints, lines, bearings and rotors minimum.

I've read about the arch of the shoe...but I dont understand why this would make it pull, and after all these years.

At one point I thought the left rear tire locked up rather than the front left. I didnt have a buddy to verify which locked first and no marks were left on the street. I do know it about ripped the steering wheel out of my hand. And scared the crap out of me. I was 3 houses down. put it in reverse and put it back in the yard. I put the car on jack stands, spun the wheels by hand, had my daughter hit the brakes..i wasnt able to turn the wheel but that doesnt say much I dont think.

When i do the brakes, i will be changing over to manual steering and plan on doing tie rods...

So my question, do I keep trouble shooting my problems with the drums or go to disk? I have $500 so far to make this happen but I would feel better knowing why it happened.

I want to drive the car this year. Funds are tight. I want matching rims and need new tires. I think I can pull off rims, tires and the swap...but like i said, why did this happen. And which way should I go.

Thanks!