400 trans shifting issue

I have a 69 Goat with a 400 engine and TH400 trans.  The linkage or something must be out of adjustment.  I cannot get the shifter all the way back into 1st gear, or "L."  It shifts down into second and all the way up to park, but it just won't go back far enough to Low.

Also, while shifting, the shifter feels too loose.  It's hard to feel where the gear actually is.  For example, when shifting from park to drive, I have to pull it back to D, and then kind of move it around and feel for the correct position of the shifter.

Are these problems related?  How do I go about fixing them?  
1969 GTO, YS code 400, 350hp/445 ft lbs of torque (stock specs), LT headers, H-pipe, 750 Holley 4160, Ignitor II ignition.  Complete Painless wiring.