Unsure of how to post link so...Google 'Chevy three speed linkage'. First YouTube is 'How to adjust three speed column shifter'. I took the information with "a grain of salt". I did not bang on the column clip cam screw and the very last step which was to lastly tighten the rear shift Rod.
If this adjustment doesn't get it and I only said to do it first as it is the easiest then I agree with truckernix. You got problems with the slop in the second gear hub synchronizer rings which are brass with a steel collar. If you choose to go that deep then figure on a repair kit with the two bearings, gaskets, thrust washers, and so on. The synchro hub is availalable as a rebuild for around 100 bucks. Also take a look at the 2nd/3rd gear shift fork where it rides on the large ring on the synchro hub. If the inside is badly worn then you can reverse it to get a better face. New it's about $35.00.
I just noticed you are in Sweden. Shipping is going to cost you big bucks. A better path might be to find a 4 speed with a floor shifter and a the kit which moves the shift lever forward.

Last edited by beltfed; 06/11/2016 1:46 AM.

Six volt guy living in a twelve volt world