Gear selector issue no third or four has anyone else had this issue sorted but the engine is smokin

the joy when I eventually saw this
https://weddleindustries.com/products/1000169/1002109

 

Quick up date I've had the engine and box out to remove the crown and repaired the linkage and I now have all gears, thanks for all your input it's much appreciated, cheers.
Having ran the van it's now smoking from the exhaust blue/white any ideas what I've done wrong?

 

White smoke is often oil down loose valve guides. Quite a few busses produce a puff when started.
If it is actually not coming out of the exhaust, the exhaust and heat exchangers may be burning off oil that has leaked on to them. My old engine produced a smoky haze from leaks onto the exhaust.

If it continues then the oil is more likely to be coming in past piston rings if no other leaks. This can happen if perfectly good pistons are swapped around.
It may also be just bedding in of new rings.

 

I hope not as it's a new engine could it do it if it was running on three because I think it's missing

 

Just let it cool down and checked all the leads and hoses nothing seems amiss. Fired it up and it all seems to have cleared only went about a mile though.
The smoke was quite heavy before, fingers crossed...........