On the cold start my tranny wont hold 1st gear. At WOT it will shift up to 2nd and then back down to 1st. I know somethings F'd up but dunno what. Like the subject says its a 700R4 out of an 86.

 

same problem on my 86...I adjusted the shift linkage and now it will hold 1st tight. It only shifts into 2nd at wot now though and it won't hold there. I need details on how to adjust it though, because it's still not right....my instructions were vague though.