hi all sorry i am new to all this i will find my way around this site in the end, i just got my 1st 109 series 3, 1973 2,1/4 petrol landy to restore and verry happy with her, my 1st problem is she only drives in 4th gear only, i have taken all the seat+floors out redy to take the gearbox off but needed to now is there anything i can check or try to see what is wrong with it befor i start taking it out it will go into all gears ok, would it be cheaper to get a nother used box or try and fix the 1 i have, thank you for your time and any help or advice