Turn signal problem 98 GMC Sierra

I have a 98 GMC Sierra K-1500 with 289k miles on it and have the weirdest problem with the turn signals. Truck has been flawless (and trouble free) up to now. I had to replace the turn/wiper/cruise
stalk due to a non functioning washer switch. Everything else was working OK. Ordered a new stalk from the dealer, took the old one out and put the new one in. Now, everything works except the turn signals, which work, but not correctly. When you turn the left blinker on, the rear left lamp flashes, but the front RIGHT and right dash light flash with the left rear. Same thing happens for the right... right rear, left front and left dash. It took 2 hours to replace this one and I hate to have to do it again twice (put the old one back in, get a new stalk from the dealer and then do it again), but i will if I have to. i almost want it to be the stalk, but I don't think it is.
Anyone ever see this before or have any suggestions? The dealer said it might be trailer wiring, but we pulled the rear 7 way plug ff completely and that didn't change anything. I'm at a loss to explain it.
HELP
Chuck
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Now, everything works except the turn

If the indicators worked fine before the multifunction switch was removed, and now you get this behavior immediately after installing the new switch, then the new switch is flaky in that one of the wires going to the two large connectors is going to the wrong place. I don't think the connectors can be pushed together the wrong way due to their design. You could pull it apart and reseat both connectors and check to see theres no wires pinched or shorted across somehow, but this is hard to imagine. It's going to have to come apart anyway so it doesn't hurt to check and reseat before actually removing and replacing again.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Chuck-one suggestion I would have is that if the dealer would work with you and 'give' you another unit-even if you paid for it with the agreement that it'll(one or the other) will be coming back-try unpulgging it under the dash(if it will-done many of these on Chevrolet S-10 Blazers and you can trouble shoot it by doing this)and then plug in the new one. Of course this will be temporary but effective in telling you if it is that 'new' unit of 'something' else. Good luck snipped-for-privacy@peru-motors.com

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

There's a good foot and a half of wiring before the two large connectors, so this might be doable from under the dash.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.