gear change

Hi, When i bought this LX450 a year ago, the shift lever had some play in it but it was manageable. Never thought of fixing it but after replacing my dashboard, the play has gotten worse. Perhaps i forced the lever back totwards R or D a bit too much to drag the dash out and never realized it...

Got a 1973 FJ40, and thinking about changing the gears to get more highway friendly. I believe it has 4.10's in it and after '79 they moved to 3:73 gears for fuel efficiency. . It has a '78 Motor, 4spd transmission and t-case Has anyone done this? What is the typical cost and who is the best...