"NOT" Like a glove

That's a "NO" on the factory A/C system they are a waste of time. Very heavy (~100 lbs.) and originally designed to run on R-12 Freon so converting to R-134a just makes them less efficient. Since you already have a 440 up front it would be wise to find ways to keep the weight down.

As far as the stall converter that depends on how good the quality is and whether or not it's designed to run "tight" when cruising around with light throttle which makes all the difference in how nice it is on the street. What brand is it?