Light Part Throttle Upshifts became variable at low speeds, rpm increased before gear changes 2-3.
After consulting Tech Manual here,I investigated and traced the problem to the rotary switch on the throttle body,
operated by the throttle linkage.
A Jo Alexander post ( Rough Shifting ) there indicated the switch should be make or break with rotation, mine was make and semi-make !
so defective.
When dismantled it was apparent that the internals were gunged up and partial contact was being permantly made.
After cleaning and re profiling the contacts, & refitting, normal light partial throttle upshifts returned.
Another example of how useful this brilliant site is.
Thanks
Paul