'85 300D vacuum modulator missing parts

[engatwork]

I pulled the existing vacuum modulator out this morning to replace it and was surprised to see that there is no modulating pressure control valve nor the spring that goes between it and the thermal thrust pin. I have had this car for a year and a half and have slowly been going through every external component of the tranny to get it to shift right. The problem with it is that it shifts into high gear by the time it gets to 30 mph. I put the existing vacuum modulator back on because there does not seem to be any problem with it. I feel that missing these parts will cause shifting issues and will get them coming over the next few days to install next weekend.

edited part In reviewing the exploded drawing in the ATSG manual at the front of the manual it shows a spring between the modulating pressure control valve and the thermal thrust pin. In a later section of the book it does not show this spring. Can anyone tell me if a spring goes in here or not. It looks like the part number for the modulating "slide" valve is 126 277 21 32.