bert transmission help

[Vanhammer]

having trouble shift into low gear, Trans has about 12nites since being rebuilt, using type f trans fluid, bleedout well ( a lot of pressure). it's just getting worse to shift. RPM range on idle is around 1200.

[Lizardracing]

IF your saying it grinds I'd be looking things that are not allowing the clutch pack to drag.
Shifter rods not proper adjusted?
Master Cylinder hanging up?
Peddle not returning?
Hyd line blockage?
Slave piston sticky in the bore?
Broken Clutch packs or reassembly error?

Have you tried shutting the car off and putting in low gear? Does the car try to pull itself as if the clutch pack isn't fully disengaged?