The other day i took my 68 out for a ride and as i came back home i had it in park on a bit of a slope so i could move my other car out of the way. Then i was ready to move it i couldnt get it to go into drive, i was able to go into reverse and neutral but the column shifter wouldnt move into the drive position. i let the car roll a bit while in neutral then i was able to get into drive. Is there a problem with my transmission or was is because i was at a bit of an angle?